start using hw again

decode rx pkts better

1 files changed, 75 insertions, 23 deletions

diff --git a/dl3.c b/dl3.c
index df09865..38b375d 100644
--- a/dl3.c
+++ b/dl3.c
@@ -8,6 +8,7 @@
 #include "libusb.h"
 
 #include "pkts.h"
+#include "hdcp.h"
 #include <openssl/bn.h>
 #include <openssl/rsa.h>
 #include <openssl/evp.h>
@@ -17,6 +18,9 @@
 
 #include <gcrypt.h>
 
+struct hdcp_session_info {
+	gcry_sexp_t pub_key;
+};
 static int VID = 0x17e9;
 static int PID = 0x4301;
 
@@ -24,7 +28,7 @@ static int PID = 0x4301;
 static unsigned char mykm[16] = { 0xcd, 0xef, 0x65, 0x33, 0x69, 0x23, 0xfa, 0x3e,
 				0x60, 0xee, 0xdd, 0x5c, 0xce, 0xfb, 0x39, 0x19 };
 
-static int create_gcrypt_pubkey(gcry_sexp_t *pub_key,
+static int create_gcrypt_pubkey(struct hdcp_session_info *info,
 				const uint8_t *n,
 				const uint8_t *e,
 				int n_len, int e_len)
@@ -55,7 +59,7 @@ static int create_gcrypt_pubkey(gcry_sexp_t *pub_key,
 
 	printf("pub key %s\n", buf);
 
-	ret = gcry_sexp_sscan(pub_key, NULL, buf, strlen(buf));
+	ret = gcry_sexp_sscan(&info->pub_key, NULL, buf, strlen(buf));
 	if (ret != 0)
 		return -1;
 	return 0;
@@ -89,9 +93,9 @@ static int create_gcrypt_km(gcry_sexp_t *km,
 	return 0;
 }
 
-static void decode_cert(const unsigned char *buf, int len, gcry_sexp_t *pub_key)
+static void decode_cert(struct hdcp_session_info *info, const uint8_t *buf, int len)
 {
-	const unsigned char *start = buf + (len - 522);
+	const uint8_t *start = buf + 2;
 	BIGNUM *e, *m;
 	int i, ret;
 	EVP_PKEY *pRsaKey = EVP_PKEY_new();
@@ -131,12 +135,14 @@ static void decode_cert(const unsigned char *buf, int len, gcry_sexp_t *pub_key)
 	}
 	printf("\n");
 
-	ret = create_gcrypt_pubkey(pub_key,
-				   &start[5],
-				   &start[133],
-				   128, 3);
-	if (ret != 0) {
-		fprintf(stderr, "failed to create pubkey %d\n", ret);
+	if (info) {
+	  ret = create_gcrypt_pubkey(info,
+				     &start[5],
+				     &start[133],
+				     128, 3);
+	  if (ret != 0) {
+	    fprintf(stderr, "failed to create pubkey %d\n", ret);
+	  }
 	}
 
 	ctx = EVP_PKEY_CTX_new(pRsaKey, NULL);
@@ -166,6 +172,54 @@ static void decode_cert(const unsigned char *buf, int len, gcry_sexp_t *pub_key)
 	printf("ret is %d\n", ret);
 }
 
+static void decode_h_prime(struct hdcp_session_info *info,
+			   const uint8_t *buf, int len)
+{
+	const uint8_t *start = buf + 1;
+	int i;
+
+	printf("h_prime: ");
+	for (i = 0; i < 32; i++) {
+		printf("%02x", start[i]);
+	}
+	printf("\n");
+
+}
+
+static void decode_rx(struct hdcp_session_info *info,
+		      const uint8_t *buf, int len)
+{
+	/**/
+	int msglen = buf[2] | (buf[3] << 8);
+	int midlen;
+
+	if (buf[0] != 0 || buf[1] != 0)
+		return;
+
+	if (buf[4] != 0x4 || buf[7] != 0x80)
+		return;
+
+	/* hdcp packet */
+	if (buf[18] != 0x84 && buf[20] != 0x30)
+		return;
+
+	switch (buf[22]) {
+	case HDCP_AKE_SEND_CERT:
+		decode_cert(info, buf + 22, len - 22);
+		break;
+	case HDCP_AKE_SEND_RRX:
+		printf("send rrx\n");
+		break;
+	case HDCP_AKE_SEND_H_PRIME:
+		decode_h_prime(info, buf + 22, len - 22);
+		break;
+	case HDCP_AKE_SEND_PAIRING_INFO:
+		printf("send pairing info\n");
+		break;
+	}
+
+}
+
 static int write_to_usb(libusb_device_handle *handle, int endpoint_out,
 			const uint8_t *buf, int len, int *size)
 {
@@ -209,6 +263,9 @@ static int send_buffer(libusb_device_handle *handle, int endpoint_out, int endpo
 	int size;
 	int len2, len;
 	gcry_sexp_t pub_key, km, result;
+	struct hdcp_session_info info;
+
+	memset(&info, 0, sizeof(info));
 
 	dl3_empty_packet(buf, &len);
 	r = write_to_usb(handle, endpoint_out, buf, len, &size);
@@ -234,26 +291,19 @@ static int send_buffer(libusb_device_handle *handle, int endpoint_out, int endpo
 	if (r < 0)
 		return r;
 
+	decode_rx(&info, buf, size);
+
 	r = block_read_usb(handle, endpoint_in, buf, &size);	
 	if (r < 0)
 		return r;
 
-	/* special cert print */
-	printf("{");
-	for (i = 0; i < size; i++) {
-		printf("0x%02x, ", buf[i]);
-		if ((i % 8) == 7)
-			printf("\n");
-	}
-	printf("}\n");
-
-	decode_cert(buf, size, &pub_key);
+	decode_rx(&info, buf, size);
 
 	r = create_gcrypt_km(&km, mykm, 16);
 	if (r != 0)
 		fprintf(stderr, "failed to create km\n");
 
-	r = gcry_pk_encrypt(&result, km, pub_key);
+	r = gcry_pk_encrypt(&result, km, info.pub_key);
 
 	GCRY_SEXP list = gcry_sexp_find_token( result, "a", 0);
 
@@ -278,6 +328,8 @@ static int send_buffer(libusb_device_handle *handle, int endpoint_out, int endpo
 		r = block_read_usb(handle, endpoint_in, buf, &size);	
 		if (r < 0)
 			return r;
+		decode_rx(&info, buf, size);
+		/* find H' */
 	} while (1);
 	return 0;
 }
@@ -336,8 +388,8 @@ int main(int argc, char** argv)
 {
 	int r;
 
-	decode_cert(dplinkcert, 546);
-#if 0
+	//	decode_cert(NULL, dplinkcert, 546);
+#if 1
 	r = libusb_init(NULL);
 	if (r < 0)
 		return r;