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authorTom Rini <trini@konsulko.com>2020-07-08 20:20:24 -0400
committerTom Rini <trini@konsulko.com>2020-07-08 20:20:24 -0400
commit61608f395e7dcb2be6060407a72a1149b046430a (patch)
tree387269e837a47126d5a7ccdef2b4d5af60598e16 /lib/tpm-v2.c
parent186529953fd10a97e6343418095edd1c535aaeb2 (diff)
parentc89b41b4db4a746647c4f0e6d33c6f4edfe96e38 (diff)
Merge branch '2020-07-08-misc-features-and-fixes'
- mem cmd improvements - TPM fixes - SPL/NAND/FIT fixes - RSA improvements
Diffstat (limited to 'lib/tpm-v2.c')
-rw-r--r--lib/tpm-v2.c44
1 files changed, 44 insertions, 0 deletions
diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c
index 5a039f65d1..a4c352e3ef 100644
--- a/lib/tpm-v2.c
+++ b/lib/tpm-v2.c
@@ -422,3 +422,47 @@ u32 tpm2_pcr_setauthvalue(struct udevice *dev, const char *pw,
return tpm_sendrecv_command(dev, command_v2, NULL, NULL);
}
+
+u32 tpm2_get_random(struct udevice *dev, void *data, u32 count)
+{
+ const u8 command_v2[10] = {
+ tpm_u16(TPM2_ST_NO_SESSIONS),
+ tpm_u32(12),
+ tpm_u32(TPM2_CC_GET_RANDOM),
+ };
+ u8 buf[COMMAND_BUFFER_SIZE], response[COMMAND_BUFFER_SIZE];
+
+ const size_t data_size_offset = 10;
+ const size_t data_offset = 12;
+ size_t response_length = sizeof(response);
+ u32 data_size;
+ u8 *out = data;
+
+ while (count > 0) {
+ u32 this_bytes = min((size_t)count,
+ sizeof(response) - data_offset);
+ u32 err;
+
+ if (pack_byte_string(buf, sizeof(buf), "sw",
+ 0, command_v2, sizeof(command_v2),
+ sizeof(command_v2), this_bytes))
+ return TPM_LIB_ERROR;
+ err = tpm_sendrecv_command(dev, buf, response,
+ &response_length);
+ if (err)
+ return err;
+ if (unpack_byte_string(response, response_length, "w",
+ data_size_offset, &data_size))
+ return TPM_LIB_ERROR;
+ if (data_size > this_bytes)
+ return TPM_LIB_ERROR;
+ if (unpack_byte_string(response, response_length, "s",
+ data_offset, out, data_size))
+ return TPM_LIB_ERROR;
+
+ count -= data_size;
+ out += data_size;
+ }
+
+ return 0;
+}