mirror of
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54 lines
1.8 KiB
C
54 lines
1.8 KiB
C
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// uC includes
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#include "../common/io.c"
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#include "../common/lib.c"
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int main () {
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char signature_buffer[64]; // >=> sp
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char *static_buffer = mem_get (0x2420); // >=> 0x2420
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puts ("Welcome to the secure program loader.");
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while (1) {
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unsigned short loadaddr; // >=> r11
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unsigned char signature_type; // >=> r9
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unsigned char payload_length; // >=> r10
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puts ("Please enter debug payload.");
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memset (static_buffer, 0, 0x400);
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getsn (static_buffer, 0x3ff);
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loadaddr = (static_buffer[0] << 8) + (static_buffer[1]);
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signature_type = static_buffer[2];
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payload_length = static_buffer[3];
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if (0x8000 > loadaddr || loadaddr >= 0xf001) {
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puts ("Load address outside allowed range of 0x8000-0xF000");
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continue;
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}
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if (payload_length - 6 > 0x3bb) {
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puts ("Invalid payload length");
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continue;
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}
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char *payload_signature = static_buffer + payload_length;
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int result;
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memcpy (signature_buffer, payload_signature, 0x40);
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if (signature_type == 0x1) {
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sha512 (static_buffer, payload_length, signature_buffer);
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result = memcmp (signature_buffer, payload_signature, 0x40);
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}
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if (signature_type != 0x0) {
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puts ("Invalid signature type");
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continue;
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} else {
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result = verify_ed25519 (mem_get (0x2400), static_buffer, payload_length, signature_buffer);
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}
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if (result != 0x1) {
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puts ("Incorrect signature, continuing");
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continue;
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}
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puts ("Signature valid, executing payload");
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memcpy (mem_get (loadaddr), static_buffer + 0x4, payload_length);
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puts ((char *) mem_get (loadaddr));
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}
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}
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