vTPM: support little endian guests

This patch makes the code endianness independent. We defined a
macro do_endian_conversion to apply endianness to raw integers
in the event entries so that they will be displayed properly.
tpm_binary_bios_measurements_show() is modified for the display.

Signed-off-by: Hon Ching(Vicky) Lo <honclo@linux.vnet.ibm.com>
Signed-off-by: Joy Latten <jmlatten@linux.vnet.ibm.com>
Reviewed-by: Ashley Lai <ashley@ahsleylai.com>
Reviewed-by: Ashley Lai <ashley@ahsleylai.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>

2 files changed, 62 insertions, 22 deletions

diff --git a/drivers/char/tpm/tpm_eventlog.c b/drivers/char/tpm/tpm_eventlog.c
index 3a56a131586c..bd72fb04225e 100644
--- a/drivers/char/tpm/tpm_eventlog.c
+++ b/drivers/char/tpm/tpm_eventlog.c
@@ -76,15 +76,25 @@ static void *tpm_bios_measurements_start(struct seq_file *m, loff_t *pos)
         void *addr = log->bios_event_log;
         void *limit = log->bios_event_log_end;
         struct tcpa_event *event;
+        u32 converted_event_size;
+        u32 converted_event_type;
+
 
         /* read over *pos measurements */
         for (i = 0; i < *pos; i++) {
                 event = addr;
 
+                converted_event_size =
+                    do_endian_conversion(event->event_size);
+                converted_event_type =
+                    do_endian_conversion(event->event_type);
+
                 if ((addr + sizeof(struct tcpa_event)) < limit) {
-                        if (event->event_type == 0 && event->event_size == 0)
+                        if ((converted_event_type == 0) &&
+                            (converted_event_size == 0))
                                 return NULL;
-                        addr += sizeof(struct tcpa_event) + event->event_size;
+                        addr += (sizeof(struct tcpa_event) +
+                                 converted_event_size);
                 }
         }
 
@@ -94,8 +104,12 @@ static void *tpm_bios_measurements_start(struct seq_file *m, loff_t *pos)
 
         event = addr;
 
-        if ((event->event_type == 0 && event->event_size == 0) ||
-            ((addr + sizeof(struct tcpa_event) + event->event_size) >= limit))
+        converted_event_size = do_endian_conversion(event->event_size);
+        converted_event_type = do_endian_conversion(event->event_type);
+
+        if (((converted_event_type == 0) && (converted_event_size == 0))
+            || ((addr + sizeof(struct tcpa_event) + converted_event_size)
+                >= limit))
                 return NULL;
 
         return addr;
@@ -107,8 +121,12 @@ static void *tpm_bios_measurements_next(struct seq_file *m, void *v,
         struct tcpa_event *event = v;
         struct tpm_bios_log *log = m->private;
         void *limit = log->bios_event_log_end;
+        u32 converted_event_size;
+        u32 converted_event_type;
 
-        v += sizeof(struct tcpa_event) + event->event_size;
+        converted_event_size = do_endian_conversion(event->event_size);
+
+        v += sizeof(struct tcpa_event) + converted_event_size;
 
         /* now check if current entry is valid */
         if ((v + sizeof(struct tcpa_event)) >= limit)
@@ -116,11 +134,11 @@ static void *tpm_bios_measurements_next(struct seq_file *m, void *v,
 
         event = v;
 
-        if (event->event_type == 0 && event->event_size == 0)
-                return NULL;
+        converted_event_size = do_endian_conversion(event->event_size);
+        converted_event_type = do_endian_conversion(event->event_type);
 
-        if ((event->event_type == 0 && event->event_size == 0) ||
-            ((v + sizeof(struct tcpa_event) + event->event_size) >= limit))
+        if (((converted_event_type == 0) && (converted_event_size == 0)) ||
+            ((v + sizeof(struct tcpa_event) + converted_event_size) >= limit))
                 return NULL;
 
         (*pos)++;
@@ -140,7 +158,7 @@ static int get_event_name(char *dest, struct tcpa_event *event,
         int i, n_len = 0, d_len = 0;
         struct tcpa_pc_event *pc_event;
 
-        switch(event->event_type) {
+        switch (do_endian_conversion(event->event_type)) {
         case PREBOOT:
         case POST_CODE:
         case UNUSED:
@@ -156,14 +174,16 @@ static int get_event_name(char *dest, struct tcpa_event *event,
         case NONHOST_CODE:
         case NONHOST_CONFIG:
         case NONHOST_INFO:
-                name = tcpa_event_type_strings[event->event_type];
+                name = tcpa_event_type_strings[do_endian_conversion
+                                                (event->event_type)];
                 n_len = strlen(name);
                 break;
         case SEPARATOR:
         case ACTION:
-                if (MAX_TEXT_EVENT > event->event_size) {
+                if (MAX_TEXT_EVENT >
+                    do_endian_conversion(event->event_size)) {
                         name = event_entry;
-                        n_len = event->event_size;
+                        n_len = do_endian_conversion(event->event_size);
                 }
                 break;
         case EVENT_TAG:
@@ -171,7 +191,7 @@ static int get_event_name(char *dest, struct tcpa_event *event,
 
                 /* ToDo Row data -> Base64 */
 
-                switch (pc_event->event_id) {
+                switch (do_endian_conversion(pc_event->event_id)) {
                 case SMBIOS:
                 case BIS_CERT:
                 case CMOS:
@@ -179,7 +199,8 @@ static int get_event_name(char *dest, struct tcpa_event *event,
                 case OPTION_ROM_EXEC:
                 case OPTION_ROM_CONFIG:
                 case S_CRTM_VERSION:
-                        name = tcpa_pc_event_id_strings[pc_event->event_id];
+                        name = tcpa_pc_event_id_strings[do_endian_conversion
+                                                        (pc_event->event_id)];
                         n_len = strlen(name);
                         break;
                 /* hash data */
@@ -188,7 +209,8 @@ static int get_event_name(char *dest, struct tcpa_event *event,
                 case OPTION_ROM_MICROCODE:
                 case S_CRTM_CONTENTS:
                 case POST_CONTENTS:
-                        name = tcpa_pc_event_id_strings[pc_event->event_id];
+                        name = tcpa_pc_event_id_strings[do_endian_conversion
+                                                        (pc_event->event_id)];
                         n_len = strlen(name);
                         for (i = 0; i < 20; i++)
                                 d_len += sprintf(&data[2*i], "%02x",
@@ -209,13 +231,24 @@ static int get_event_name(char *dest, struct tcpa_event *event,
 static int tpm_binary_bios_measurements_show(struct seq_file *m, void *v)
 {
         struct tcpa_event *event = v;
-        char *data = v;
+        struct tcpa_event temp_event;
+        char *tempPtr;
         int i;
 
-        for (i = 0; i < sizeof(struct tcpa_event) + event->event_size; i++)
-                seq_putc(m, data[i]);
+        memcpy(&temp_event, event, sizeof(struct tcpa_event));
+
+        /* convert raw integers for endianness */
+        temp_event.pcr_index = do_endian_conversion(event->pcr_index);
+        temp_event.event_type = do_endian_conversion(event->event_type);
+        temp_event.event_size = do_endian_conversion(event->event_size);
+
+        tempPtr = (char *)&temp_event;
+
+        for (i = 0; i < sizeof(struct tcpa_event) + temp_event.event_size; i++)
+                seq_putc(m, tempPtr[i]);
 
         return 0;
+
 }
 
 static int tpm_bios_measurements_release(struct inode *inode,
@@ -238,7 +271,7 @@ static int tpm_ascii_bios_measurements_show(struct seq_file *m, void *v)
         char *eventname;
         struct tcpa_event *event = v;
         unsigned char *event_entry =
-            (unsigned char *) (v + sizeof(struct tcpa_event));
+            (unsigned char *)(v + sizeof(struct tcpa_event));
 
         eventname = kmalloc(MAX_TEXT_EVENT, GFP_KERNEL);
         if (!eventname) {
@@ -247,13 +280,14 @@ static int tpm_ascii_bios_measurements_show(struct seq_file *m, void *v)
                 return -EFAULT;
         }
 
-        seq_printf(m, "%2d ", event->pcr_index);
+        /* 1st: PCR */
+        seq_printf(m, "%2d ", do_endian_conversion(event->pcr_index));
 
         /* 2nd: SHA1 */
         seq_printf(m, "%20phN", event->pcr_value);
 
         /* 3rd: event type identifier */
-        seq_printf(m, " %02x", event->event_type);
+        seq_printf(m, " %02x", do_endian_conversion(event->event_type));
 
         len += get_event_name(eventname, event, event_entry);
 
diff --git a/drivers/char/tpm/tpm_eventlog.h b/drivers/char/tpm/tpm_eventlog.h
index e7da086d6928..267bfbd1b7bb 100644
--- a/drivers/char/tpm/tpm_eventlog.h
+++ b/drivers/char/tpm/tpm_eventlog.h
@@ -6,6 +6,12 @@
 #define MAX_TEXT_EVENT          1000    /* Max event string length */
 #define ACPI_TCPA_SIG           "TCPA"  /* 0x41504354 /'TCPA' */
 
+#ifdef CONFIG_PPC64
+#define do_endian_conversion(x) be32_to_cpu(x)
+#else
+#define do_endian_conversion(x) x
+#endif
+
 enum bios_platform_class {
         BIOS_CLIENT = 0x00,
         BIOS_SERVER = 0x01,