cli send encrypted & manage megolm session, save/load megolm sessions

[matrix_esp_thesis] / src / matrix.c

diff --git a/src/matrix.c b/src/matrix.c
index 082806a73c55ef1518d8bd8300ba51bb1e38b2bd..fa7303f891e250dfc5d1349e6293ee8bf4d5a7ff 100644 (file)
--- a/src/matrix.c
+++ b/src/matrix.c
@@ -1,27 +1,1101 @@
 #include "matrix.h"\r
 \r
 #include "matrix.h"\r
 \r

+#include <time.h>\r
+#include <stdio.h>\r
+#include <mjson.h>\r
+\r
+\r
+#define LOGIN_REQUEST_SIZE 1024\r
+#define LOGIN_RESPONSE_SIZE 1024\r
+#define LOGIN_URL "/_matrix/client/v3/login"\r
+\r
+#define ENCRYPTED_REQUEST_SIZE (1024*5)\r
+#define ENCRYPTED_EVENT_SIZE (1024*10)\r
+#define ROOMEVENT_REQUEST_SIZE 256\r
+#define ROOMEVENT_RESPONSE_SIZE 1024\r
+#define ROOMEVENT_URL "/_matrix/client/v3/rooms/%s/send/%s/%d"\r
+\r
+#define TODEVICE_EVENT_SIZE (1024*5)\r
+#define TODEVICE_URL "/_matrix/client/v3/sendToDevice/%s/%d"\r
+\r
+#define KEYS_QUERY_URL "/_matrix/client/v3/keys/query"\r
+#define KEYS_QUERY_REQUEST_SIZE 256\r
+#define KEYS_QUERY_RESPONSE_SIZE (1024*10)\r
+\r
+#define KEYS_UPLOAD_URL "/_matrix/client/v3/keys/upload"\r
+#define KEYS_UPLOAD_REQUEST_SIZE 1024\r
+#define KEYS_UPLOAD_REQUEST_SIGNED_SIZE 2048\r
+#define KEYS_UPLOAD_RESPONSE_SIZE 2048\r
+\r
+#define KEYS_CLAIM_URL "/_matrix/client/v3/keys/claim"\r
+#define KEYS_CLAIM_REQUEST_SIZE 1024\r
+#define KEYS_CLAIM_RESPONSE_SIZE 1024\r
+\r
+#define JSON_QUERY_SIZE 128\r
+\r
+\r
+\r
+void\r
+Randomize(\r
+    uint8_t * random,\r
+    int randomLen)\r
+{\r
+    static bool first = true;\r
+    if (first) { srand(time(0)); first = false; }\r
+\r
+    for (int i = 0; i < randomLen; i++)\r
+    {\r
+        random[i] = rand() % 256;\r
+    }\r
+}\r
+\r
+bool\r
+JsonEscape(\r
+    const char * sIn, int sInLen,\r
+    char * sOut, int sOutCap)\r
+{\r
+    int sOutIndex = 0;\r
+\r
+    for (int i = 0; i < sInLen; i++)\r
+    {\r
+        if (i >= sOutCap)\r
+            return false;\r
+        \r
+        if (sIn[i] == '.' ||\r
+            sIn[i] == '[' ||\r
+            sIn[i] == ']'\r
+        ) {\r
+            sOut[sOutIndex++] = '\\';\r
+        }\r
+        sOut[sOutIndex++] = sIn[i];\r
+    }\r
+\r
+    if (sOutIndex < sOutCap)\r
+        sOut[sOutIndex] = '\0';\r
+\r
+    return true;\r
+}\r
+\r
+bool JsonSign(\r
+    MatrixClient * client,\r
+    const char * sIn, int sInLen,\r
+    char * sOut, int sOutCap)\r
+{\r
+    static char signature[OLM_SIGNATURE_SIZE];\r
+    size_t res =\r
+        olm_account_sign(client->olmAccount.account,\r
+            sIn, sInLen,\r
+            signature, OLM_SIGNATURE_SIZE);\r
+    \r
+    int signatureLen = res;\r
+\r
+    static char signatureJson[JSON_SIGNATURE_SIZE];\r
+    int signatureJsonLen =\r
+        mjson_snprintf(signatureJson, JSON_SIGNATURE_SIZE,\r
+            "{"\r
+                "\"signatures\":{"\r
+                    "\"%s\":{"\r
+                        "\"ed25519:%s\":\"%.*s\""\r
+                    "}"\r
+                "}"\r
+            "}",\r
+            client->userId,\r
+            client->deviceId,\r
+            signatureLen, signature);\r
+\r
+    struct mjson_fixedbuf result = { sOut, sOutCap, 0 };\r
+    mjson_merge(\r
+        sIn, sInLen,\r
+        signatureJson, signatureJsonLen,\r
+        mjson_print_fixed_buf,\r
+        &result);\r
+\r
+    return true;\r
+}\r
+\r
+\r
+bool\r
+MatrixOlmAccountInit(\r
+    MatrixOlmAccount * account)\r
+{\r
+    account->account = olm_account(account->memory);\r
+\r
+    static uint8_t random[OLM_ACCOUNT_RANDOM_SIZE];\r
+    Randomize(random, OLM_ACCOUNT_RANDOM_SIZE);\r
+\r
+    size_t res = olm_create_account(\r
+        account->account,\r
+        random,\r
+        OLM_ACCOUNT_RANDOM_SIZE);\r
+\r
+    return res != olm_error();\r
+}\r
+\r
+// TODO: in/outbound sessions\r
+bool\r
+MatrixOlmSessionTo(\r
+    MatrixOlmSession * session,\r
+    OlmAccount * olmAccount,\r
+    const char * deviceId,\r
+    const char * deviceKey,\r
+    const char * deviceOnetimeKey)\r
+{\r
+    memset(session, 0, sizeof(MatrixOlmSession));\r
+\r
+    session->deviceId = deviceId;\r
+\r
+    session->session =\r
+        olm_session(session->memory);\r
+\r
+    static uint8_t random[OLM_OUTBOUND_SESSION_RANDOM_SIZE];\r
+    Randomize(random, OLM_OUTBOUND_SESSION_RANDOM_SIZE);\r
+\r
+    size_t res =\r
+        olm_create_outbound_session(session->session,\r
+            olmAccount,\r
+            deviceKey, strlen(deviceKey),\r
+            deviceOnetimeKey, strlen(deviceOnetimeKey),\r
+            random, OLM_OUTBOUND_SESSION_RANDOM_SIZE);\r
+    \r
+    if (res == olm_error()) {\r
+        printf("error olm: %s\n", olm_account_last_error(olmAccount));\r
+    }\r
+\r
+    return session->session != NULL;\r
+}\r
+\r
+bool\r
+MatrixOlmSessionEncrypt(\r
+    MatrixOlmSession * session,\r
+    const char * plaintext,\r
+    char * outBuffer, int outBufferCap)\r
+{\r
+    static uint8_t random[OLM_ENCRYPT_RANDOM_SIZE];\r
+    Randomize(random, OLM_ENCRYPT_RANDOM_SIZE);\r
+\r
+    size_t res = olm_encrypt(session->session,\r
+        plaintext, strlen(plaintext),\r
+        random, OLM_ENCRYPT_RANDOM_SIZE,\r
+        outBuffer, outBufferCap);\r
+\r
+    return res != olm_error();\r
+}\r
+\r
+// https://matrix.org/docs/guides/end-to-end-encryption-implementation-guide#starting-a-megolm-session\r
+bool\r
+MatrixMegolmOutSessionInit(\r
+    MatrixMegolmOutSession * session,\r
+    const char * roomId)\r
+{\r
+    memset(session, 0, sizeof(MatrixMegolmOutSession));\r
+\r
+    static uint8_t random[MEGOLM_INIT_RANDOM_SIZE];\r
+    Randomize(random, MEGOLM_INIT_RANDOM_SIZE);\r
+\r
+    session->roomId = roomId;\r
+\r
+    session->session =\r
+        olm_outbound_group_session(session->memory);\r
+\r
+    olm_init_outbound_group_session(\r
+        session->session,\r
+        random,\r
+        MEGOLM_INIT_RANDOM_SIZE);\r
+\r
+    olm_outbound_group_session_id(session->session,\r
+        (uint8_t *)session->id,\r
+        MEGOLM_SESSION_ID_SIZE);\r
+        \r
+    olm_outbound_group_session_key(session->session,\r
+        (uint8_t *)session->key,\r
+        MEGOLM_SESSION_KEY_SIZE);\r
+    \r
+    return true;\r
+}\r
+\r
+bool\r
+MatrixMegolmOutSessionEncrypt(\r
+    MatrixMegolmOutSession * session,\r
+    const char * plaintext,\r
+    char * outBuffer, int outBufferCap)\r
+{\r
+    size_t res = olm_group_encrypt(session->session,\r
+        (uint8_t *)plaintext, strlen(plaintext),\r
+        (uint8_t *)outBuffer, outBufferCap);\r
+\r
+    return res != olm_error();\r
+}\r
+\r
+bool\r
+MatrixMegolmOutSessionSave(\r
+    MatrixMegolmOutSession * session,\r
+    const char * filename,\r
+    const char * key)\r
+{\r
+    FILE * f = fopen(filename, "w");\r
+\r
+    size_t roomIdLen = strlen(session->roomId);\r
+    fwrite(&roomIdLen, sizeof(size_t), 1, f);\r
+    fwrite(session->roomId, 1, roomIdLen, f);\r
+\r
+    size_t pickleBufferLen =\r
+        olm_pickle_outbound_group_session_length(\r
+            session->session);\r
+    void * pickleBuffer = malloc(pickleBufferLen);\r
+\r
+    olm_pickle_outbound_group_session(\r
+        session->session,\r
+        key, strlen(key),\r
+        pickleBuffer, pickleBufferLen);\r
+    \r
+    fwrite(&pickleBufferLen, sizeof(size_t), 1, f);\r
+    fwrite(pickleBuffer, 1, pickleBufferLen, f);\r
+    free(pickleBuffer);\r
+\r
+    fclose(f);\r
+\r
+    return true;\r
+}\r
+\r
+bool\r
+MatrixMegolmOutSessionLoad(\r
+    MatrixMegolmOutSession * session,\r
+    const char * filename,\r
+    const char * key)\r
+{\r
+    FILE * f = fopen(filename, "r");\r
+\r
+    size_t roomIdLen;\r
+    fread(&roomIdLen, sizeof(size_t), 1, f);\r
+    fread(session->roomId, 1, roomIdLen, f);\r
+\r
+    size_t pickleBufferLen;\r
+    fread(&pickleBufferLen, sizeof(size_t), 1, f);\r
+\r
+    void * pickleBuffer = malloc(pickleBufferLen);\r
+    fread(pickleBuffer, 1, pickleBufferLen, f);\r
+\r
+    olm_unpickle_outbound_group_session(\r
+        session->session,\r
+        key, strlen(key),\r
+        pickleBuffer, pickleBufferLen);\r
+    \r
+    free(pickleBuffer);\r
+\r
+    fclose(f);\r
+\r
+    return true;\r
+}\r
+\r
+\r

 \r
 bool\r
 MatrixClientInit(\r
     MatrixClient * client,\r
 \r
 bool\r
 MatrixClientInit(\r
     MatrixClient * client,\r

-    FixedBuffer server\r
-) {\r
+    const char * server)\r
+{\r
+    memset(client, 0, sizeof(MatrixClient));\r
+\r
+    strcpy(client->server, server);\r
+\r
+    // init olm account\r
+    MatrixOlmAccountInit(&client->olmAccount);\r
+\r
+    // set device key\r
+    static char deviceKeysJson[OLM_IDENTITY_KEYS_JSON_SIZE];\r
+    size_t res =\r
+        olm_account_identity_keys(\r
+            client->olmAccount.account,\r
+            deviceKeysJson,\r
+            OLM_IDENTITY_KEYS_JSON_SIZE);\r
+\r
+    mjson_get_string(deviceKeysJson, res,\r
+        "$.curve25519",\r
+        client->deviceKey, DEVICE_KEY_SIZE);\r
+    mjson_get_string(deviceKeysJson, res,\r
+        "$.ed25519",\r
+        client->signingKey, SIGNING_KEY_SIZE);\r
+\r
+    return true;\r
+}\r
+\r
+bool\r
+MatrixClientSave(\r
+    MatrixClient * client,\r
+    const char * filename)\r
+{\r
+    FILE * f = fopen(filename, "w");\r
+    \r
+    fwrite(client->deviceKey, 1, DEVICE_KEY_SIZE, f);\r
+    fwrite(client->signingKey, 1, DEVICE_KEY_SIZE, f);\r
+    fwrite(client->userId, 1, USER_ID_SIZE, f);\r
+    fwrite(client->server, 1, SERVER_SIZE, f);\r
+    fwrite(client->accessToken, 1, ACCESS_TOKEN_SIZE, f);\r
+    fwrite(client->deviceId, 1, DEVICE_ID_SIZE, f);\r
+    fwrite(client->expireMs, 1, EXPIRE_MS_SIZE, f);\r
+    fwrite(client->refreshToken, 1, REFRESH_TOKEN_SIZE, f);\r
+\r
+    fwrite(&client->numDevices, sizeof(int), 1, f);\r
+    for (int i = 0; i < client->numDevices; i++) {\r
+        fwrite(client->devices[i].deviceId, 1, DEVICE_ID_SIZE, f);\r
+        fwrite(client->devices[i].deviceKey, 1, DEVICE_KEY_SIZE, f);\r
+    }\r
+\r
+    fclose(f);\r
+    return true;\r
+}\r
+\r
+bool\r
+MatrixClientLoad(\r
+    MatrixClient * client,\r
+    const char * filename)\r
+{\r
+    FILE * f = fopen(filename, "r");\r
+    \r
+    fread(client->deviceKey, 1, DEVICE_KEY_SIZE, f);\r
+    fread(client->signingKey, 1, DEVICE_KEY_SIZE, f);\r
+    fread(client->userId, 1, USER_ID_SIZE, f);\r
+    fread(client->server, 1, SERVER_SIZE, f);\r
+    fread(client->accessToken, 1, ACCESS_TOKEN_SIZE, f);\r
+    fread(client->deviceId, 1, DEVICE_ID_SIZE, f);\r
+    fread(client->expireMs, 1, EXPIRE_MS_SIZE, f);\r
+    fread(client->refreshToken, 1, REFRESH_TOKEN_SIZE, f);\r
+\r
+    fread(&client->numDevices, sizeof(int), 1, f);\r
+    for (int i = 0; i < client->numDevices; i++) {\r
+        fread(client->devices[i].deviceId, 1, DEVICE_ID_SIZE, f);\r
+        fread(client->devices[i].deviceKey, 1, DEVICE_KEY_SIZE, f);\r
+    }\r
+\r
+    fclose(f);\r
+    return true;\r
+}\r
+\r
+bool\r
+MatrixClientSetAccessToken(\r
+    MatrixClient * client,\r
+    const char * accessToken)\r
+{\r
+    for (int i = 0; i < ACCESS_TOKEN_SIZE-1; i++)\r
+        client->accessToken[i] = accessToken[i];\r
+    client->accessToken[ACCESS_TOKEN_SIZE-1] = '\0';\r
+\r
+    return true;\r
+}\r
+\r
+bool\r
+MatrixClientSetDeviceId(\r
+    MatrixClient * client,\r
+    const char * deviceId)\r
+{\r
+    for (int i = 0; i < DEVICE_ID_SIZE-1; i++)\r
+        client->deviceId[i] = deviceId[i];\r
+    client->deviceId[DEVICE_ID_SIZE-1] = '\0';\r
+\r
+    return true;\r
+}\r
+\r
+bool\r
+MatrixClientSetUserId(\r
+    MatrixClient * client,\r
+    const char * userId)\r
+{\r
+    for (int i = 0; i < USER_ID_SIZE-1; i++)\r
+        client->userId[i] = userId[i];\r
+    client->userId[USER_ID_SIZE-1] = '\0';\r
+\r
+    return true;\r
+}\r
+\r
+bool\r
+MatrixClientGenerateOnetimeKeys(\r
+    MatrixClient * client,\r
+    int numberOfKeys)\r
+{\r
+    static uint8_t random[OLM_ONETIME_KEYS_RANDOM_SIZE];\r
+    Randomize(random, OLM_ONETIME_KEYS_RANDOM_SIZE);\r

 \r
 \r

+    size_t res =\r
+        olm_account_generate_one_time_keys(client->olmAccount.account,\r
+            numberOfKeys, random, OLM_ONETIME_KEYS_RANDOM_SIZE);\r
+\r
+    return res != olm_error();\r
+}\r
+\r
+// https://spec.matrix.org/v1.7/client-server-api/#post_matrixclientv3keysupload\r
+bool\r
+MatrixClientUploadOnetimeKeys(\r
+    MatrixClient * client)\r
+{\r
+    static char requestBuffer[KEYS_UPLOAD_REQUEST_SIZE];\r
+\r
+    mjson_snprintf(requestBuffer, KEYS_UPLOAD_REQUEST_SIZE,\r
+        "{\"one_time_keys\":{");\r
+\r
+    static char onetimeKeysBuffer[1024];\r
+    olm_account_one_time_keys(client->olmAccount.account,\r
+        onetimeKeysBuffer, 1024);\r
+\r
+    const char *keys;\r
+    int keysLen;\r
+    mjson_find(onetimeKeysBuffer, strlen(onetimeKeysBuffer), "$.curve25519", &keys, &keysLen);\r
+\r
+    int koff, klen, voff, vlen, vtype, off = 0;\r
+    while ((off = mjson_next(keys, keysLen, off, &koff, &klen, &voff, &vlen, &vtype)) != 0) {\r
+        static char keyJson[JSON_ONETIME_KEY_SIZE];\r
+        \r
+        snprintf(keyJson, JSON_ONETIME_KEY_SIZE,\r
+            "{\"key\":\"%.*s\"}",\r
+            vlen-2, keys + voff+1);\r
+\r
+        static char keyJsonSigned[JSON_ONETIME_KEY_SIGNED_SIZE];\r
+\r
+        JsonSign(client,\r
+            keyJson, JSON_ONETIME_KEY_SIZE,\r
+            keyJsonSigned, JSON_ONETIME_KEY_SIGNED_SIZE);\r
+        \r
+        mjson_snprintf(requestBuffer+strlen(requestBuffer), KEYS_UPLOAD_REQUEST_SIZE-strlen(requestBuffer),\r
+            "\"signed_curve25519:%.*s\":%s,",\r
+            klen-2, keys + koff+1,\r
+            keyJsonSigned);\r
+    }\r
+\r
+    mjson_snprintf(requestBuffer+strlen(requestBuffer)-1, KEYS_UPLOAD_REQUEST_SIZE-strlen(requestBuffer),\r
+        "}}");\r
+\r
+    static char responseBuffer[KEYS_UPLOAD_RESPONSE_SIZE];\r
+    MatrixHttpPost(client,\r
+        KEYS_UPLOAD_URL,\r
+        requestBuffer,\r
+        responseBuffer, KEYS_UPLOAD_RESPONSE_SIZE,\r
+        true);\r
+\r
+    return true;\r
+}\r
+\r
+// https://spec.matrix.org/v1.7/client-server-api/#post_matrixclientv3keysupload\r
+bool\r
+MatrixClientUploadDeviceKeys(\r
+    MatrixClient * client)\r
+{\r
+    static char deviceKeysBuffer[KEYS_UPLOAD_REQUEST_SIZE];\r
+\r
+    mjson_snprintf(deviceKeysBuffer, KEYS_UPLOAD_REQUEST_SIZE,\r
+        "{\"device_keys\":{"\r
+            "\"algorithms\":[\"m.olm.v1.curve25519-aes-sha2\",\"m.megolm.v1.aes-sha2\"],"\r
+            "\"device_id\":\"%s\","\r
+            "\"keys\":{"\r
+                "\"curve25519:%s\":\"%s\","\r
+                "\"ed25519:%s\":\"%s\""\r
+            "},"\r
+            "\"user_id\":\"%s\""\r
+        "}}",\r
+        client->deviceId,\r
+        client->deviceId, client->deviceKey,\r
+        client->deviceId, client->signingKey,\r
+        client->userId);\r
+\r
+    static char deviceKeysSignedBuffer[KEYS_UPLOAD_REQUEST_SIGNED_SIZE];\r
+    JsonSign(client,\r
+        deviceKeysBuffer, KEYS_UPLOAD_REQUEST_SIZE,\r
+        deviceKeysSignedBuffer, KEYS_UPLOAD_REQUEST_SIZE);\r
+\r
+\r
+    static char responseBuffer[KEYS_UPLOAD_RESPONSE_SIZE];\r
+    MatrixHttpPost(client,\r
+        KEYS_UPLOAD_URL,\r
+        deviceKeysSignedBuffer,\r
+        responseBuffer, KEYS_UPLOAD_RESPONSE_SIZE,\r
+        true);\r
+\r
+    return true;\r

 }\r
 \r
 }\r
 \r

+// https://spec.matrix.org/v1.7/client-server-api/#post_matrixclientv3keysclaim\r
+bool\r
+MatrixClientClaimOnetimeKey(\r
+    MatrixClient * client,\r
+    const char * userId,\r
+    const char * deviceId,\r
+    char * outOnetimeKey, int outOnetimeKeyCap)\r
+{\r
+    static char requestBuffer[KEYS_CLAIM_REQUEST_SIZE];\r
+    mjson_snprintf(requestBuffer, KEYS_CLAIM_REQUEST_SIZE,\r
+    "{"\r
+      "\"one_time_keys\": {"\r
+        "\"%s\": {"\r
+          "\"%s\": \"signed_curve25519\""\r
+        "}"\r
+      "},"\r
+      "\"timeout\": 10000"\r
+    "}",\r
+    userId,\r
+    deviceId);\r
+\r
+    static char responseBuffer[KEYS_CLAIM_RESPONSE_SIZE];\r
+    MatrixHttpPost(client,\r
+        KEYS_CLAIM_URL,\r
+        requestBuffer,\r
+        responseBuffer, KEYS_CLAIM_RESPONSE_SIZE,\r
+        true);\r
+    \r
+    char userIdEscaped[USER_ID_SIZE];\r
+    JsonEscape(userId, strlen(userId),\r
+        userIdEscaped, USER_ID_SIZE);\r
+    \r
+    static char query[JSON_QUERY_SIZE];\r
+    snprintf(query, JSON_QUERY_SIZE,\r
+        "$.one_time_keys.%s.%s",\r
+        userIdEscaped,\r
+        deviceId);\r
+    \r
+    const char * keyObject;\r
+    int keyObjectSize;\r
+    mjson_find(responseBuffer, strlen(responseBuffer),\r
+        query,\r
+        &keyObject, &keyObjectSize);\r
+    \r
+    int koff, klen, voff, vlen, vtype;\r
+    mjson_next(keyObject, keyObjectSize, 0,\r
+        &koff, &klen, &voff, &vlen, &vtype);\r
+    \r
+    mjson_get_string(keyObject + voff, vlen,\r
+        "$.key", outOnetimeKey, outOnetimeKeyCap);\r
+    \r
+    // TODO: verify signature\r
+    \r
+    return true;\r
+}\r
+\r
+// https://spec.matrix.org/v1.6/client-server-api/#post_matrixclientv3login\r

 bool\r
 MatrixClientLoginPassword(\r
     MatrixClient * client,\r
 bool\r
 MatrixClientLoginPassword(\r
     MatrixClient * client,\r

-    FixedBuffer username,\r
-    FixedBuffer password\r
-) {\r
+    const char * username,\r
+    const char * password,\r
+    const char * displayName)\r
+{\r
+    static char requestBuffer[LOGIN_REQUEST_SIZE];\r
+\r
+    mjson_snprintf(requestBuffer, LOGIN_REQUEST_SIZE,\r
+        "{"\r
+            "\"type\": \"m.login.password\","\r
+            "\"identifier\": {"\r
+                "\"type\": \"m.id.user\","\r
+                "\"user\": \"%s\""\r
+            "},"\r
+            "\"password\": \"%s\","\r
+            "\"initial_device_display_name\": \"%s\""\r
+        "}",\r
+        username,\r
+        password,\r
+        displayName);\r
+    \r
+    static char responseBuffer[LOGIN_RESPONSE_SIZE];\r
+    bool result =\r
+        MatrixHttpPost(client,\r
+            LOGIN_URL,\r
+            requestBuffer,\r
+            responseBuffer, LOGIN_RESPONSE_SIZE,\r
+            false);\r
+    \r
+    int responseLen = strlen(responseBuffer);\r
+    \r
+    if (!result)\r
+        return false;\r
+\r
+    mjson_get_string(responseBuffer, responseLen,\r
+        "$.access_token",\r
+        client->accessToken, ACCESS_TOKEN_SIZE);\r
+    mjson_get_string(responseBuffer, responseLen,\r
+        "$.device_id",\r
+        client->deviceId, DEVICE_ID_SIZE);\r
+    mjson_get_string(responseBuffer, responseLen,\r
+        "$.expires_in_ms",\r
+        client->expireMs, EXPIRE_MS_SIZE);\r
+    mjson_get_string(responseBuffer, responseLen,\r
+        "$.refresh_token",\r
+        client->refreshToken, REFRESH_TOKEN_SIZE);\r
+\r
+    return true;\r
+}\r
+\r
+// https://spec.matrix.org/v1.6/client-server-api/#put_matrixclientv3roomsroomidsendeventtypetxnid\r
+bool\r
+MatrixClientSendEvent(\r
+    MatrixClient * client,\r
+    const char * roomId,\r
+    const char * msgType,\r
+    const char * msgBody)\r
+{    \r
+    static char requestUrl[MAX_URL_LEN];\r
+    sprintf(requestUrl,\r
+        ROOMEVENT_URL, roomId, msgType, (int)time(NULL));\r
+\r
+    static char responseBuffer[ROOMEVENT_RESPONSE_SIZE];\r
+    bool result =\r
+        MatrixHttpPut(client,\r
+            requestUrl,\r
+            msgBody,\r
+            responseBuffer, ROOMEVENT_RESPONSE_SIZE,\r
+            true);\r
+    \r
+    return result;\r
+}\r
+\r
+// https://spec.matrix.org/v1.6/client-server-api/#mroomencrypted\r
+// https://matrix.org/docs/guides/end-to-end-encryption-implementation-guide#sending-an-encrypted-message-event\r
+bool\r
+MatrixClientSendEventEncrypted(\r
+    MatrixClient * client,\r
+    const char * roomId,\r
+    const char * msgType,\r
+    const char * msgBody)\r
+{\r
+    // event json\r
+    static char requestBuffer[ROOMEVENT_REQUEST_SIZE];\r
+    sprintf(requestBuffer,\r
+        "{"\r
+        "\"type\":\"%s\","\r
+        "\"content\":%s,"\r
+        "\"room_id\":\"%s\""\r
+        "}",\r
+        msgType,\r
+        msgBody,\r
+        roomId);\r
+\r
+    // get megolm session\r
+    MatrixMegolmOutSession * outSession;\r
+    MatrixClientGetMegolmOutSession(client, roomId, &outSession);\r
+        \r
+    // encrypt\r
+    static char encryptedBuffer[ENCRYPTED_REQUEST_SIZE];\r
+    MatrixMegolmOutSessionEncrypt(outSession,\r
+        requestBuffer,\r
+        encryptedBuffer, ENCRYPTED_REQUEST_SIZE);\r
+\r
+    // encrypted event json\r
+    const char * senderKey = client->deviceKey;\r
+    const char * sessionId = outSession->id;\r
+    const char * deviceId = client->deviceId;\r
+\r
+    static char encryptedEventBuffer[ENCRYPTED_EVENT_SIZE];\r
+    sprintf(encryptedEventBuffer,\r
+        "{"\r
+        "\"algorithm\":\"m.megolm.v1.aes-sha2\","\r
+        "\"ciphertext\":\"%s\","\r
+        "\"device_id\":\"%s\","\r
+        "\"sender_key\":\"%s\","\r
+        "\"session_id\":\"%s\""\r
+        "}",\r
+        encryptedBuffer,\r
+        deviceId,\r
+        senderKey,\r
+        sessionId);\r
+\r
+    // send\r
+    return MatrixClientSendEvent(client,\r
+        roomId,\r
+        "m.room.encrypted",\r
+        encryptedEventBuffer);\r
+}\r
+\r
+// https://spec.matrix.org/v1.6/client-server-api/#get_matrixclientv3sync\r
+bool\r
+MatrixClientSync(\r
+    MatrixClient * client,\r
+    char * outSyncBuffer, int outSyncCap)\r
+{\r
+    return\r
+        MatrixHttpGet(client,\r
+            "/_matrix/client/v3/sync",\r
+            outSyncBuffer, outSyncCap,\r
+            true);\r
+}\r
+\r
+bool\r
+MatrixClientShareMegolmOutSession(\r
+    MatrixClient * client,\r
+    const char * userId,\r
+    const char * deviceId,\r
+    MatrixMegolmOutSession * session)\r
+{\r
+    // generate room key event\r
+    static char eventBuffer[KEY_SHARE_EVENT_LEN];\r
+    sprintf(eventBuffer,\r
+        "{"\r
+            "\"algorithm\":\"m.megolm.v1.aes-sha2\","\r
+            "\"room_id\":\"%s\","\r
+            "\"session_id\":\"%s\","\r
+            "\"session_key\":\"%s\""\r
+        "}",\r
+        session->roomId,\r
+        session->id,\r
+        session->key\r
+    );\r
+\r
+    // // get olm session\r
+    // MatrixOlmSession * olmSession;\r
+    // MatrixClientGetOlmSession(client, userId, deviceId, &olmSession);\r
+\r
+    // // encrypt\r
+    // char encryptedBuffer[KEY_SHARE_EVENT_LEN];\r
+    // MatrixOlmSessionEncrypt(olmSession,\r
+    //     eventBuffer,\r
+    //     encryptedBuffer, KEY_SHARE_EVENT_LEN);\r
+\r
+    // send\r
+    MatrixClientSendToDeviceEncrypted(client,\r
+        userId,\r
+        deviceId,\r
+        eventBuffer,\r
+        "m.room_key");\r
+\r
+    return true;\r
+}\r
+\r
+bool\r
+MatrixClientShareMegolmOutSessionTest(\r
+    MatrixClient * client,\r
+    const char * deviceId,\r
+    MatrixMegolmOutSession * session)\r
+{\r
+    // generate room key event\r
+    char eventBuffer[KEY_SHARE_EVENT_LEN];\r
+    sprintf(eventBuffer,\r
+        "{"\r
+            "\"algorithm\":\"m.megolm.v1.aes-sha2\","\r
+            "\"room_id\":\"%s\","\r
+            "\"session_id\":\"%s\","\r
+            "\"session_key\":\"%s\""\r
+        "}",\r
+        session->roomId,\r
+        session->id,\r
+        session->key\r
+    );\r
+\r
+    // send\r
+    MatrixClientSendToDevice(client,\r
+        client->userId,\r
+        deviceId,\r
+        eventBuffer,\r
+        "m.room_key");\r
+\r
+    return true;\r
+}\r
+\r
+// bool\r
+// MatrixClientSetMegolmOutSession(\r
+//     MatrixClient * client,\r
+//     const char * roomId,\r
+//     MatrixMegolmOutSession session)\r
+// {\r
+//     if (client->numMegolmOutSessions < 10)\r
+//     {\r
+//         session.roomId = roomId;\r
+//         client->megolmOutSessions[client->numMegolmOutSessions] = session;\r
+//         client->numMegolmOutSessions++;\r
+\r
+//         return true;\r
+//     }\r
+//     return false;\r
+// }\r
+\r
+bool\r
+MatrixClientGetMegolmOutSession(\r
+    MatrixClient * client,\r
+    const char * roomId,\r
+    MatrixMegolmOutSession ** outSession)\r
+{\r
+    for (int i = 0; i < client->numMegolmOutSessions; i++)\r
+    {\r
+        if (strcmp(client->megolmOutSessions[i].roomId, roomId) == 0)\r
+        {\r
+            *outSession = &client->megolmOutSessions[i];\r
+            return true;\r
+        }\r
+    }\r
+\r
+    if (client->numMegolmOutSessions < NUM_MEGOLM_SESSIONS)\r
+    {\r
+        MatrixMegolmOutSessionInit(\r
+            &client->megolmOutSessions[client->numMegolmOutSessions],\r
+            roomId);\r
+\r
+        *outSession = &client->megolmOutSessions[client->numMegolmOutSessions];\r
+        \r
+        client->numMegolmOutSessions++;\r
+\r
+        return true;\r
+    }\r
+\r
+    return false;\r
+}\r
+\r
+bool\r
+MatrixClientGetOlmSession(\r
+    MatrixClient * client,\r
+    const char * userId,\r
+    const char * deviceId,\r
+    MatrixOlmSession ** outSession)\r
+{\r
+    for (int i = 0; i < client->numOlmSessions; i++)\r
+    {\r
+        if (strcmp(client->olmSessions[i].deviceId, deviceId) == 0)\r
+        {\r
+            *outSession = &client->olmSessions[i];\r
+            return true;\r
+        }\r
+    }\r
+\r
+    if (client->numOlmSessions < NUM_OLM_SESSIONS)\r
+    {\r
+        static char deviceKey[DEVICE_KEY_SIZE];\r
+        MatrixClientGetDeviceKey(client,\r
+            deviceId,\r
+            deviceKey, DEVICE_KEY_SIZE);\r
+\r
+        char onetimeKey[ONETIME_KEY_SIZE];\r
+        MatrixClientClaimOnetimeKey(client,\r
+            userId,\r
+            deviceId,\r
+            onetimeKey, ONETIME_KEY_SIZE);\r
+\r
+        MatrixOlmSessionTo(\r
+            &client->olmSessions[client->numOlmSessions],\r
+            client->olmAccount.account,\r
+            deviceId,\r
+            deviceKey,\r
+            onetimeKey);\r
+\r
+        *outSession = &client->olmSessions[client->numOlmSessions];\r
+        \r
+        client->numOlmSessions++;\r
+\r
+        return true;\r
+    }\r
+\r
+    return false;\r
+}\r
+\r
+// https://spec.matrix.org/v1.6/client-server-api/#put_matrixclientv3sendtodeviceeventtypetxnid\r
+bool\r
+MatrixClientSendToDevice(\r
+    MatrixClient * client,\r
+    const char * userId,\r
+    const char * deviceId,\r
+    const char * message,\r
+    const char * msgType)\r
+{\r
+    static char requestUrl[MAX_URL_LEN];\r
+    sprintf(requestUrl,\r
+        TODEVICE_URL, msgType, (int)time(NULL));\r

 \r
 \r

+    static char eventBuffer[TODEVICE_EVENT_SIZE];\r
+    snprintf(eventBuffer, TODEVICE_EVENT_SIZE,\r
+        "{"\r
+            "\"messages\": {"\r
+                "\"%s\": {"\r
+                    "\"%s\":%s"\r
+                "}"\r
+            "}"\r
+        "}",\r
+        userId,\r
+        deviceId,\r
+        message);\r
+\r
+    static char responseBuffer[ROOMEVENT_RESPONSE_SIZE];\r
+    bool result =\r
+        MatrixHttpPut(client,\r
+            requestUrl,\r
+            eventBuffer,\r
+            responseBuffer, ROOMEVENT_RESPONSE_SIZE,\r
+            true);\r
+    \r
+    return result;\r
+}\r
+\r
+bool\r
+MatrixClientSendToDeviceEncrypted(\r
+    MatrixClient * client,\r
+    const char * userId,\r
+    const char * deviceId,\r
+    const char * message,\r
+    const char * msgType)\r
+{\r
+    // get olm session\r
+    MatrixOlmSession * olmSession;\r
+    MatrixClientGetOlmSession(client, userId, deviceId, &olmSession);\r
+\r
+    // create event json\r
+    char deviceKey[DEVICE_KEY_SIZE];\r
+    MatrixClientGetDeviceKey(client, deviceId, deviceKey, DEVICE_KEY_SIZE);\r
+    \r
+    static char eventBuffer[TODEVICE_EVENT_SIZE];\r
+    sprintf(eventBuffer,\r
+        "{"\r
+        "\"type\": \"%s\","\r
+        "\"content\": \"%s\","\r
+        "\"sender\": \"%s\","\r
+        "\"recipient\": \"%s\","\r
+        "\"recipient_keys\": {"\r
+          "\"ed25519\": \"%s\""\r
+        "},"\r
+        "\"keys\": {"\r
+          "\"ed25519\": \"%s\""\r
+        "}"\r
+        "}",\r
+        msgType,\r
+        message,\r
+        client->userId,\r
+        userId, // recipient user id\r
+        deviceKey, // recipient device key\r
+        client->deviceKey);\r
+\r
+    // encrypt\r
+    static char encryptedBuffer[ENCRYPTED_REQUEST_SIZE];\r
+    MatrixOlmSessionEncrypt(olmSession,\r
+        eventBuffer,\r
+        encryptedBuffer, ENCRYPTED_REQUEST_SIZE);\r
+\r
+    static char encryptedEventBuffer[ENCRYPTED_EVENT_SIZE];\r
+    sprintf(encryptedEventBuffer,\r
+        "{"\r
+        "\"algorithm\":\"m.olm.v1.curve25519-aes-sha2\","\r
+        "\"ciphertext\":{"\r
+          "\"%s\":{"\r
+            "\"body\":\"%s\","\r
+            "\"type\":%d"\r
+          "}"\r
+        "},"\r
+        "\"device_id\":\"%s\","\r
+        "\"sender_key\":\"%s\""\r
+        "}",\r
+        deviceKey,\r
+        encryptedBuffer,\r
+        0, //olmSession->type,\r
+        client->deviceId,\r
+        client->deviceKey);\r
+\r
+    // send\r
+    return MatrixClientSendToDevice(\r
+        client,\r
+        userId,\r
+        deviceId,\r
+        encryptedEventBuffer,\r
+        "m.room.encrypted");\r
+}\r
+\r
+bool\r
+MatrixClientFindDevice(\r
+    MatrixClient * client,\r
+    const char * deviceId,\r
+    MatrixDevice ** outDevice)\r
+{\r
+    MatrixClientRequestDeviceKeys(client);\r
+\r
+    for (int i = 0; i < client->numDevices; i++)\r
+    {\r
+        if (strcmp(client->devices[i].deviceId, deviceId) == 0)\r
+        {\r
+            *outDevice = &client->devices[i];\r
+            return true;\r
+        }\r
+    }\r
+\r
+    *outDevice = NULL;\r
+    return false;\r

 }\r
 \r
 bool\r
 }\r
 \r
 bool\r

-MatrixClientGetAccessToken(\r
+MatrixClientGetDeviceKey(\r

     MatrixClient * client,\r
     MatrixClient * client,\r

-    FixedBuffer * outBuffer\r
-) {\r
+    const char * deviceId,\r
+    char * outDeviceKey, int outDeviceKeyCap)\r
+{\r
+    MatrixDevice * device;\r
+    \r
+    if (MatrixClientFindDevice(client, deviceId, &device))\r
+    {\r
+        strncpy(outDeviceKey, device->deviceKey, outDeviceKeyCap);\r
+        return true;\r
+    }\r
+\r
+    MatrixClientRequestDeviceKeys(client);\r
+    \r
+    if (MatrixClientFindDevice(client, deviceId, &device))\r
+    {\r
+        strncpy(outDeviceKey, device->deviceKey, outDeviceKeyCap);\r
+        return true;\r
+    }\r
+\r
+    return false;\r
+}\r
+\r
+// https://spec.matrix.org/v1.6/client-server-api/#post_matrixclientv3keysquery\r
+bool\r
+MatrixClientRequestDeviceKeys(\r
+    MatrixClient * client)\r
+{\r
+    static char userIdEscaped[USER_ID_SIZE];\r
+    JsonEscape(client->userId, strlen(client->userId),\r
+        userIdEscaped, USER_ID_SIZE);\r
+\r
+    static char request[KEYS_QUERY_REQUEST_SIZE];\r
+    snprintf(request, KEYS_QUERY_REQUEST_SIZE,\r
+        "{\"device_keys\":{\"%s\":[]}}", client->userId);\r
+\r
+    static char responseBuffer[KEYS_QUERY_RESPONSE_SIZE];\r
+    bool requestResult = MatrixHttpPost(client,\r
+        KEYS_QUERY_URL,\r
+        request,\r
+        responseBuffer, KEYS_QUERY_RESPONSE_SIZE,\r
+        true);\r
+\r
+    if (! requestResult)\r
+        return false;\r
+\r
+    // query for retrieving device keys for user id\r
+    static char query[JSON_QUERY_SIZE];\r
+    snprintf(query, JSON_QUERY_SIZE,\r
+        "$.device_keys.%s", userIdEscaped);\r
+    \r
+    const char * s;\r
+    int slen;\r
+    mjson_find(responseBuffer, strlen(responseBuffer),\r
+        query, &s, &slen);\r
+\r
+    // loop over keys\r
+    \r
+    int koff, klen, voff, vlen, vtype, off = 0;\r
+    for (off = 0; (off = mjson_next(s, slen, off, &koff, &klen,\r
+                                    &voff, &vlen, &vtype)) != 0; ) {\r
+        const char * key = s + koff;\r
+        const char * val = s + voff;\r
+\r
+        // set device id, "key" is the JSON key\r
+        MatrixDevice d;\r
+        snprintf(d.deviceId, DEVICE_ID_SIZE,\r
+            "%.*s", klen-2, key+1);\r
+\r
+        // look for device key in value\r
+        static char deviceKeyQuery[JSON_QUERY_SIZE];\r
+        snprintf(deviceKeyQuery, JSON_QUERY_SIZE,\r
+            "$.keys.curve25519:%s", d.deviceId);\r
+        mjson_get_string(val, vlen,\r
+            deviceKeyQuery, d.deviceKey, DEVICE_KEY_SIZE);\r
+\r
+        // add device\r
+        if (client->numDevices < NUM_DEVICES)\r
+        {\r
+            client->devices[client->numDevices] = d;\r
+            client->numDevices++;\r
+        }\r
+        else\r
+        {\r
+            return false;\r
+        }\r
+    }\r

 \r
 \r

+    return true;\r

 }\r
 }\r