From: Joshua Wise <joshua@ainfvec.fac.cs.cmu.edu>
Date: Sat, 3 Oct 2009 06:40:29 +0000 (-0400)
Subject: Fix smm_type detection to actually detect, and add a state_num_regs routine.
X-Git-Url: http://git.joshuawise.com/netwatch.git/commitdiff_plain/3cfffb8916ccc8aaeab1589804f8eab919d932c3?hp=4e3ef36be657e274f91162edbbf13265abb23319

Fix smm_type detection to actually detect, and add a state_num_regs routine.
---

diff --git a/include/state.h b/include/state.h
index 9bc4b90..8bfb96d 100644
--- a/include/state.h
+++ b/include/state.h
@@ -122,6 +122,7 @@ enum smm_type state_get_type(void);
 uint64_t state_get_reg (enum state_reg_t reg);
 int state_reg_size (enum state_reg_t reg);
 int state_set_reg (enum state_reg_t reg, uint64_t value);
+int state_num_regs();
 
 int state_dump_reg(char * dest, int max, enum state_reg_t reg);
 
diff --git a/lib/state.c b/lib/state.c
index 46a56e8..9a14efc 100644
--- a/lib/state.c
+++ b/lib/state.c
@@ -72,7 +72,7 @@ static const uint32_t offset_table_legacy[] = {
 	[STATE_REG_IDT_BASE]	= 0xff94 | SZ_DWORD
 };
 
-#define MAX_REG_LEGACY (sizeof(offset_table_legacy)/sizeof(uint32_t))
+#define MAX_REG_LEGACY (sizeof(offset_table_legacy)/sizeof(offset_table_legacy[0]) - 1)
 
 static const uint32_t offset_table_amd64[] = {
 	[STATE_REV]		= 0xfefc | SZ_DWORD,
@@ -207,9 +207,9 @@ static const char register_names[][4] = {
 	[STATE_REG_EFER]	= "EFER"
 };
 
-#define MAX_REG_AMD64 (sizeof(offset_table_amd64)/sizeof(uint32_t))
+#define MAX_REG_AMD64 (sizeof(offset_table_amd64)/sizeof(offset_table_amd64[0]) - 1)
 
-static enum smm_type smm_type = SMM_TYPE_64;
+static enum smm_type smm_type = SMM_TYPE_UNKNOWN;
 
 /* Probe CPUID to figure out what kind of processor this actually is.
  * We memoize this in 'smm_type', so cpuid only needs to happen once.
@@ -245,9 +245,9 @@ static unsigned long get_offset(enum state_reg_t reg) {
 
 	check_smm_type();
 
-	if (smm_type == SMM_TYPE_32 && reg < MAX_REG_LEGACY)
+	if (smm_type == SMM_TYPE_32 && reg <= MAX_REG_LEGACY)
 		return offset_table_legacy[reg];
-	else if (smm_type == SMM_TYPE_64 && reg < MAX_REG_AMD64)
+	else if (smm_type == SMM_TYPE_64 && reg <= MAX_REG_AMD64)
 		return offset_table_amd64[reg];
 	else
 		return 0;
@@ -355,3 +355,13 @@ int state_dump_reg(char * dest, int max, enum state_reg_t reg) {
 		return 0;
 	}
 }
+
+int state_num_regs() {
+	check_smm_type();
+
+	if (smm_type == SMM_TYPE_32)
+		return MAX_REG_LEGACY;
+	else if (smm_type == SMM_TYPE_64)
+		return MAX_REG_AMD64;
+	return 0;
+}