Change argument types in se.c/h, implement read32le/be, etc.

.gitignore

@@ -50,3 +50,5 @@ modules.order
 Module.symvers
 Mkfile.old
 dkms.conf
+
+.*/

exosphere/se.c

@@ -1,10 +1,9 @@
-#include <stdint.h>
-
 #include "utils.h"
+#include "cache.h"
 #include "se.h"
 
-void trigger_se_rsa_op(void *buf, unsigned int size);
-void trigger_se_aes_op(unsigned int op, char *dst, unsigned int dst_size, const unsigned char *src, unsigned int src_size);
+void trigger_se_rsa_op(void *buf, size_t size);
+void trigger_se_aes_op(unsigned int op, void *dst, size_t dst_size, const void *src, size_t src_size);
 
 /* Globals for driver. */
 volatile security_engine_t *g_security_engine;
@@ -97,30 +96,30 @@ void clear_rsa_keyslot(unsigned int keyslot) {
     }
 }
 
-void set_aes_keyslot(unsigned int keyslot, const unsigned char *key, unsigned int key_size) {
+void set_aes_keyslot(unsigned int keyslot, const void *key, size_t key_size) {
     if (g_security_engine == NULL || keyslot >= KEYSLOT_AES_MAX || key_size > KEYSIZE_AES_MAX) {
         panic();
     }
     
-    for (unsigned int i = 0; i < (key_size >> 2); i++) {
+    for (size_t i = 0; i < (key_size >> 2); i++) {
         g_security_engine->AES_KEYTABLE_ADDR = (keyslot << 4) | i;
         g_security_engine->AES_KEYTABLE_DATA = read32le(key, 4 * i);
     }
 }
 
-void set_rsa_keyslot(unsigned int keyslot, const unsigned char *modulus, unsigned int modulus_size, const unsigned char *exp, unsigned int exp_size) {
+void set_rsa_keyslot(unsigned int keyslot, const void  *modulus, size_t modulus_size, const void *exponent, size_t exp_size) {
     if (g_security_engine == NULL || keyslot >= KEYSLOT_RSA_MAX || modulus_size > KEYSIZE_RSA_MAX || exp_size > KEYSIZE_RSA_MAX) {
         panic();
     }
     
-    for (unsigned int i = 0; i < (modulus_size >> 2); i++) {
+    for (size_t i = 0; i < (modulus_size >> 2); i++) {
         g_security_engine->RSA_KEYTABLE_ADDR = (keyslot << 7) | 0x40 | i;
         g_security_engine->RSA_KEYTABLE_DATA = read32be(modulus, 4 * i);
     }
     
-    for (unsigned int i = 0; i < (exp_size >> 2); i++) {
+    for (size_t i = 0; i < (exp_size >> 2); i++) {
         g_security_engine->RSA_KEYTABLE_ADDR = (keyslot << 7) | i;
-        g_security_engine->RSA_KEYTABLE_DATA = read32be(exp, 4 * i);
+        g_security_engine->RSA_KEYTABLE_DATA = read32be(exponent, 4 * i);
     }
     
     g_se_modulus_sizes[keyslot] = modulus_size;
@@ -128,18 +127,18 @@ void set_rsa_keyslot(unsigned int keyslot, const unsigned char *modulus, unsigne
 }
 
 
-void set_aes_keyslot_iv(unsigned int keyslot, const unsigned char *iv, unsigned int iv_size) {
+void set_aes_keyslot_iv(unsigned int keyslot, const void *iv, size_t iv_size) {
     if (g_security_engine == NULL || keyslot >= KEYSLOT_AES_MAX || iv_size > 0x10) {
         panic();
     }
     
-    for (unsigned int i = 0; i < (iv_size >> 2); i++) {
+    for (size_t i = 0; i < (iv_size >> 2); i++) {
         g_security_engine->AES_KEYTABLE_ADDR = (keyslot << 4) | 8 | i;
         g_security_engine->AES_KEYTABLE_DATA = read32le(iv, 4 * i);
     }
 }
 
-void set_se_ctr(const char *ctr) {
+void set_se_ctr(const void *ctr) {
     if (g_security_engine == NULL) {
         panic();
     }
@@ -149,7 +148,7 @@ void set_se_ctr(const char *ctr) {
     }
 }
 
-void decrypt_data_into_keyslot(unsigned int keyslot_dst, unsigned int keyslot_src, const unsigned char *wrapped_key, unsigned int wrapped_key_size) {
+void decrypt_data_into_keyslot(unsigned int keyslot_dst, unsigned int keyslot_src, const void *wrapped_key, size_t wrapped_key_size) {
     if (g_security_engine == NULL || keyslot_dst >= KEYSLOT_AES_MAX || keyslot_src >= KEYSIZE_AES_MAX || wrapped_key_size > KEYSIZE_AES_MAX) {
         panic();
     }
@@ -157,38 +156,37 @@ void decrypt_data_into_keyslot(unsigned int keyslot_dst, unsigned int keyslot_sr
     g_security_engine->CONFIG_REG = (ALG_AES_DEC | DST_KEYTAB);
     g_security_engine->CRYPTO_REG = keyslot_src << 24;
     g_security_engine->BLOCK_COUNT_REG = 0;
-    g_se_callback->CRYPTO_KEYTABLE_DST_REG = keyslot_dst << 8;
-    
-    /* TODO: Cache flush the wrapped key. */
-    
+    g_security_engine->CRYPTO_KEYTABLE_DST_REG = keyslot_dst << 8;
+
+    flush_dcache_range(wrapped_key, (const uint8_t *)wrapped_key + wrapped_key_size);
     trigger_se_aes_op(OP_START, NULL, 0, wrapped_key, wrapped_key_size);
 }
 
 
-void se_crypt_aes(unsigned int keyslot, unsigned char *dst, unsigned int dst_size, const unsigned char *src, unsigned int src_size, unsigned int config, unsigned int mode, unsigned int (*callback)(void));
+void se_crypt_aes(unsigned int keyslot, void *dst, size_t dst_size, const void *src, size_t src_size, unsigned int config, unsigned int mode, unsigned int (*callback)(void));
 
-void se_exp_mod(unsigned int keyslot, unsigned char *buf, unsigned int size, unsigned int (*callback)(void)) {
-    unsigned char stack_buf[KEYSIZE_RSA_MAX];
+void se_exp_mod(unsigned int keyslot, void *buf, size_t size, unsigned int (*callback)(void)) {
+    uint8_t stack_buf[KEYSIZE_RSA_MAX];
     
     if (g_security_engine == NULL || keyslot >= KEYSLOT_RSA_MAX || size > KEYSIZE_RSA_MAX) {
         panic();
     }
     
     /* Endian swap the input. */
-    for (unsigned int i = size; i > 0; i--) {
-        stack_buf[i] = buf[size - i];
+    for (size_t i = size; i > 0; i--) {
+        stack_buf[i] = *((uint8_t *)buf + size - i);
     }
     
-    /* TODO: Flush cache for stack copy. */
-    
+
     g_security_engine->CONFIG_REG = (ALG_RSA | DST_RSAREG);
     g_security_engine->RSA_CONFIG = keyslot << 24;
     g_security_engine->RSA_KEY_SIZE_REG = (g_se_modulus_sizes[keyslot] >> 6) - 1;
     g_security_engine->RSA_EXP_SIZE_REG = g_se_exp_sizes[keyslot] >> 2;
-    
+
     set_security_engine_callback(callback);
-    
+
+    flush_dcache_range(stack_buf, stack_buf + KEYSIZE_RSA_MAX);
     trigger_se_rsa_op(stack_buf, size);
-    
+
     while (!(g_security_engine->INT_STATUS_REG & 2)) { /* Wait a while */ }
-}
+}

exosphere/se.h

@@ -1,6 +1,9 @@
 #ifndef EXOSPHERE_SE_H
 #define EXOSPHERE_SE_H
 
+#include <stdint.h>
+#include <stddef.h>
+
 /* Exosphere driver for the Tegra X1 security engine. */
 
 #define KEYSLOT_AES_MAX 0x10
@@ -100,18 +103,18 @@ void set_rsa_keyslot_flags(unsigned int keyslot, unsigned int flags);
 void clear_aes_keyslot(unsigned int keyslot);
 void clear_rsa_keyslot(unsigned int keyslot);
 
-void set_aes_keyslot(unsigned int keyslot, const unsigned char *key, unsigned int key_size);
-void decrypt_data_into_keyslot(unsigned int keyslot_dst, unsigned int keyslot_src, const unsigned char *wrapped_key, unsigned int wrapped_key_size);
-void set_rsa_keyslot(unsigned int keyslot, const unsigned char *modulus, unsigned int modulus_size, const unsigned char *exp, unsigned int exp_size);
-void set_aes_keyslot_iv(unsigned int keyslot, const unsigned char *iv, unsigned int iv_size);
-void set_se_ctr(const char *ctr);
+void set_aes_keyslot(unsigned int keyslot, const void *key, size_t key_size);
+void decrypt_data_into_keyslot(unsigned int keyslot_dst, unsigned int keyslot_src, const void *wrapped_key, size_t wrapped_key_size);
+void set_rsa_keyslot(unsigned int keyslot, const void *modulus, size_t modulus_size, const void *exponent, size_t exp_size);
+void set_aes_keyslot_iv(unsigned int keyslot, const void *iv, size_t iv_size);
+void set_se_ctr(const void *ctr);
 
-void se_crypt_aes(unsigned int keyslot, unsigned char *dst, unsigned int dst_size, const unsigned char *src, unsigned int src_size, unsigned int config, unsigned int mode, unsigned int (*callback)(void));
-void se_exp_mod(unsigned int keyslot, unsigned char *buf, unsigned int size, unsigned int (*callback)(void));
+void se_crypt_aes(unsigned int keyslot, void *dst, size_t dst_size, const void *src, size_t src_size, unsigned int config, unsigned int mode, unsigned int (*callback)(void));
+void se_exp_mod(unsigned int keyslot, void *buf, size_t size, unsigned int (*callback)(void));
 
-void se_generate_random(unsigned int keyslot, unsigned char *dst, unsigned int size);
+void se_generate_random(unsigned int keyslot, void *dst, size_t size);
 
 /* TODO: SE context save API, consider extending AES API for secure world vs non-secure world operations. */
 /* In particular, smc_crypt_aes takes in raw DMA lists, and we need to support that. */
 
-#endif /* EXOSPHERE_SE_H */
+#endif /* EXOSPHERE_SE_H */

exosphere/smc_user.c

@@ -6,10 +6,8 @@
 #include "se.h"
 
 uint32_t user_load_aes_key(smc_args_t *args) {
-    unsigned char sealed_kek[0x10];
-    unsigned char wrapped_key[0x10];
-    uint64_t *p_sealed_kek = (uint64_t *)(&sealed_kek[0]);
-    uint64_t *p_wrapped_key = (uint64_t *)(&wrapped_key[0]);
+    uint64_t sealed_kek[2];
+    uint64_t wrapped_key[2];
     
     uint32_t keyslot = (uint32_t)args->X[1];
     if (keyslot > 3) {
@@ -17,10 +15,10 @@ uint32_t user_load_aes_key(smc_args_t *args) {
     }
     
     /* Copy keydata */
-    p_sealed_kek[0] = args->X[2];
-    p_sealed_kek[1] = args->X[3];
-    p_wrapped_key[0] = args->X[4];
-    p_wrapped_key[1] = args->X[5];
+    sealed_kek[0] = args->X[2];
+    sealed_kek[1] = args->X[3];
+    wrapped_key[0] = args->X[4];
+    wrapped_key[1] = args->X[5];
     
     /* TODO: Unseal the kek. */
     set_aes_keyslot(9, sealed_kek, 0x10);
@@ -28,4 +26,4 @@ uint32_t user_load_aes_key(smc_args_t *args) {
     /* Unwrap the key. */
     decrypt_data_into_keyslot(keyslot, 9, wrapped_key, 0x10);
     return 0;
-}
+}

exosphere/utils.h

@@ -2,16 +2,22 @@
 #define EXOSPHERE_UTILS_H
 
 #include <stdint.h>
+#include <stddef.h>
 
 void panic(void);
 
-unsigned int read32le(const unsigned char *dword, unsigned int offset);
-unsigned int read32be(const unsigned char *dword, unsigned int offset);
+static inline uint32_t read32le(const void *dword, size_t offset) {
+    return *(uint32_t *)((uintptr_t)dword + offset);
+}
 
-static inline uint32_t get_core_id(void) {
-    uint32_t core_id;
-    asm volatile("mrs %0, MPIDR_EL1" : "=r"(core_id));
+static inline uint32_t read32be(const unsigned char *dword, size_t offset) {
+    return __builtin_bswap32(read32le(dword, offset));
+}
+
+static inline unsigned int get_core_id(void) {
+    unsigned int core_id;
+    __asm__ __volatile__ ("mrs %0, MPIDR_EL1" : "=r"(core_id));
     return core_id;
 }
 
-#endif
+#endif