Date/Time EIP-712 filtering implementation

src_features/signMessageEIP712/commands_712.c

@@ -28,6 +28,7 @@
 #define P2_IMPL_FIELD             P2_DEF_FIELD
 #define P2_FILT_ACTIVATE          0x00
 #define P2_FILT_MESSAGE_INFO      0x0F
+#define P2_FILT_DATE_TIME         0xFC
 #define P2_FILT_AMOUNT_JOIN_TOKEN 0xFD
 #define P2_FILT_AMOUNT_JOIN_VALUE 0xFE
 #define P2_FILT_RAW_FIELD         0xFF
@@ -177,6 +178,9 @@ bool handle_eip712_filtering(const uint8_t *const apdu_buf) {
                 reply_apdu = false;
             }
             break;
+        case P2_FILT_DATE_TIME:
+            ret = filtering_date_time(&apdu_buf[OFFSET_CDATA], apdu_buf[OFFSET_LC]);
+            break;
         case P2_FILT_AMOUNT_JOIN_TOKEN:
             ret = filtering_amount_join_token(&apdu_buf[OFFSET_CDATA], apdu_buf[OFFSET_LC]);
             break;

src_features/signMessageEIP712/filtering.c

@@ -14,6 +14,7 @@
 #define FILT_MAGIC_MESSAGE_INFO      183
 #define FILT_MAGIC_AMOUNT_JOIN_TOKEN 11
 #define FILT_MAGIC_AMOUNT_JOIN_VALUE 22
+#define FILT_MAGIC_DATETIME          33
 #define FILT_MAGIC_RAW_FIELD         72
 
 /**
@@ -214,6 +215,66 @@ bool filtering_message_info(const uint8_t *payload, uint8_t length) {
     return true;
 }
 
+/**
+ * Command to display a field as a date-time
+ *
+ * @param[in] payload the payload to parse
+ * @param[in] length the payload length
+ * @return whether it was successful or not
+ */
+bool filtering_date_time(const uint8_t *payload, uint8_t length) {
+    uint8_t name_len;
+    const char *name;
+    uint8_t sig_len;
+    const uint8_t *sig;
+    uint8_t offset = 0;
+
+    if (path_get_root_type() != ROOT_MESSAGE) {
+        apdu_response_code = APDU_RESPONSE_CONDITION_NOT_SATISFIED;
+        return false;
+    }
+
+    // Parsing
+    if ((offset + sizeof(name_len)) > length) {
+        return false;
+    }
+    name_len = payload[offset++];
+    if ((offset + name_len) > length) {
+        return false;
+    }
+    name = (char *) &payload[offset];
+    offset += name_len;
+    if ((offset + sizeof(sig_len)) > length) {
+        return false;
+    }
+    sig_len = payload[offset++];
+    if ((offset + sig_len) != length) {
+        return false;
+    }
+    sig = &payload[offset];
+
+    // Verification
+    cx_sha256_t hash_ctx;
+    if (!sig_verif_start(&hash_ctx, FILT_MAGIC_DATETIME)) {
+        return false;
+    }
+    hash_filtering_path((cx_hash_t *) &hash_ctx);
+    hash_nbytes((uint8_t *) name, sizeof(char) * name_len, (cx_hash_t *) &hash_ctx);
+    if (!sig_verif_end(&hash_ctx, sig, sig_len)) {
+        return false;
+    }
+
+    // Handling
+    if (!check_typename("uint")) {
+        return false;
+    }
+    if (name_len > 0) {  // don't substitute for an empty name
+        ui_712_set_title(name, name_len);
+    }
+    ui_712_flag_field(true, name_len > 0, false, true);
+    return true;
+}
+
 /**
  * Command to display a field as an amount-join (token part)
  *
@@ -261,7 +322,7 @@ bool filtering_amount_join_token(const uint8_t *payload, uint8_t length) {
     if (!check_typename("address") || !check_token_index(token_idx)) {
         return false;
     }
-    ui_712_flag_field(false, false, true);
+    ui_712_flag_field(false, false, true, false);
     ui_712_token_join_prepare_addr_check(token_idx);
     return true;
 }
@@ -328,7 +389,7 @@ bool filtering_amount_join_value(const uint8_t *payload, uint8_t length) {
     if (!check_typename("uint") || !check_token_index(token_idx)) {
         return false;
     }
-    ui_712_flag_field(false, false, true);
+    ui_712_flag_field(false, false, true, false);
     ui_712_token_join_prepare_amount(token_idx, name, name_len);
     return true;
 }
@@ -386,7 +447,7 @@ bool filtering_raw_field(const uint8_t *payload, uint8_t length) {
     if (name_len > 0) {  // don't substitute for an empty name
         ui_712_set_title(name, name_len);
     }
-    ui_712_flag_field(true, name_len > 0, false);
+    ui_712_flag_field(true, name_len > 0, false, false);
     return true;
 }
 

src_features/signMessageEIP712/filtering.h

@@ -7,6 +7,7 @@
 #include <stdint.h>
 
 bool filtering_message_info(const uint8_t *payload, uint8_t length);
+bool filtering_date_time(const uint8_t *payload, uint8_t length);
 bool filtering_amount_join_token(const uint8_t *payload, uint8_t length);
 bool filtering_amount_join_value(const uint8_t *payload, uint8_t length);
 bool filtering_raw_field(const uint8_t *payload, uint8_t length);

src_features/signMessageEIP712/ui_logic.c

@@ -2,6 +2,7 @@
 
 #include <stdlib.h>
 #include <stdbool.h>
+#include <time.h>
 #include "ui_logic.h"
 #include "mem.h"
 #include "mem_utils.h"
@@ -39,6 +40,7 @@ typedef enum {
 #define UI_712_FIELD_SHOWN         (1 << 0)
 #define UI_712_FIELD_NAME_PROVIDED (1 << 1)
 #define UI_712_AMOUNT_JOIN         (1 << 2)
+#define UI_712_DATETIME            (1 << 3)
 
 typedef struct {
     s_amount_join joins[MAX_ITEMS];
@@ -426,6 +428,42 @@ static bool update_amount_join(const uint8_t *data, uint8_t length) {
     return true;
 }
 
+/**
+ * Format given data as a human-readable date/time representation
+ *
+ * @param[in] data the data that needs formatting
+ * @param[in] length its length
+ * @return whether it was successful or not
+ */
+static bool ui_712_format_datetime(const uint8_t *data, uint8_t length) {
+    struct tm tstruct;
+    int shown_hour;
+    time_t timestamp = u64_from_BE(data, length);
+
+    if (gmtime_r(&timestamp, &tstruct) == NULL) {
+        return false;
+    }
+    if (tstruct.tm_hour == 0) {
+        shown_hour = 12;
+    } else {
+        shown_hour = tstruct.tm_hour;
+        if (shown_hour > 12) {
+            shown_hour -= 12;
+        }
+    }
+    snprintf(strings.tmp.tmp,
+             sizeof(strings.tmp.tmp),
+             "%04d-%02d-%02d\n%02d:%02d:%02d %s UTC",
+             tstruct.tm_year + 1900,
+             tstruct.tm_mon + 1,
+             tstruct.tm_mday,
+             shown_hour,
+             tstruct.tm_min,
+             tstruct.tm_sec,
+             (tstruct.tm_hour < 12) ? "AM" : "PM");
+    return true;
+}
+
 /**
  * Used to notify of a new field to review in the current struct (key + value)
  *
@@ -497,6 +535,12 @@ bool ui_712_new_field(const void *const field_ptr, const uint8_t *const data, ui
         }
     }
 
+    if (ui_ctx->field_flags & UI_712_DATETIME) {
+        if (!ui_712_format_datetime(data, length)) {
+            return false;
+        }
+    }
+
     // Check if this field is supposed to be displayed
     if (ui_712_field_shown()) {
         ui_712_redraw_generic_step();
@@ -573,8 +617,9 @@ unsigned int ui_712_reject() {
  * @param[in] show if this field should be shown on the device
  * @param[in] name_provided if a substitution name has been provided
  * @param[in] token_join if this field is part of a token join
+ * @param[in] datetime if this field should be shown and formatted as a date/time
  */
-void ui_712_flag_field(bool show, bool name_provided, bool token_join) {
+void ui_712_flag_field(bool show, bool name_provided, bool token_join, bool datetime) {
     if (show) {
         ui_ctx->field_flags |= UI_712_FIELD_SHOWN;
     }
@@ -584,6 +629,9 @@ void ui_712_flag_field(bool show, bool name_provided, bool token_join) {
     if (token_join) {
         ui_ctx->field_flags |= UI_712_AMOUNT_JOIN;
     }
+    if (datetime) {
+        ui_ctx->field_flags |= UI_712_DATETIME;
+    }
 }
 
 /**

src_features/signMessageEIP712/ui_logic.h

@@ -26,7 +26,7 @@ void ui_712_set_title(const char *const str, uint8_t length);
 void ui_712_set_value(const char *const str, uint8_t length);
 void ui_712_message_hash(void);
 void ui_712_redraw_generic_step(void);
-void ui_712_flag_field(bool show, bool name_provided, bool token_join);
+void ui_712_flag_field(bool show, bool name_provided, bool token_join, bool datetime);
 void ui_712_field_flags_reset(void);
 void ui_712_finalize_field(void);
 void ui_712_set_filtering_mode(e_eip712_filtering_mode mode);