Merge pull request #21 from slp/sev-launch-measurement

sev: add a utility for generating SEV LMs

utils/Makefile

@@ -0,0 +1,9 @@
+.PHONY: clean
+
+all: sev_launch_measurement
+
+sev_launch_measurement: sev_launch_measurement.c
+	gcc -o $@ $< -lcrypto
+
+clean:
+	rm -rf sev_launch_measurement

utils/sev_launch_measurement.c

@@ -0,0 +1,79 @@
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <dlfcn.h>
+#include <openssl/sha.h>
+
+
+int SHA256_Init(SHA256_CTX *c);
+int SHA256_Update(SHA256_CTX *c, const void *data, size_t len);
+int SHA256_Final(unsigned char *md, SHA256_CTX *c);
+unsigned char *SHA256(const unsigned char *d, size_t n,
+                       unsigned char *md);
+
+int main(int argc, char **argv)
+{
+    char * (*krunfw_get_kernel) (size_t *load_addr, size_t *size);
+    char * (*krunfw_get_initrd) (size_t *size);
+    char * (*krunfw_get_qboot) (size_t *size);
+    char *payload_addr;
+    size_t payload_size;
+    size_t load_addr;
+    void *handle;
+    SHA256_CTX shactx;
+    char digest[33];
+    int i;
+
+    if (argc != 2) {
+        printf("Usage: %s LIBKRUNFW_SO\n", argv[0]);
+        exit(-1);
+    }
+
+    handle = dlopen(argv[1], RTLD_NOW);
+    if (handle == NULL) {
+        perror("Couldn't open library");
+        exit(-1);
+    }
+
+    krunfw_get_kernel = dlsym(handle, "krunfw_get_kernel");
+    if (krunfw_get_kernel == NULL) {
+        perror("Couldn't find krunfw_get_kernel symbol");
+        exit(-1);
+    }
+
+    krunfw_get_initrd = dlsym(handle, "krunfw_get_initrd");
+    if (krunfw_get_initrd == NULL) {
+        perror("Couldn't find krunfw_get_initrd symbol");
+        exit(-1);
+    }
+
+    krunfw_get_qboot = dlsym(handle, "krunfw_get_qboot");
+    if (krunfw_get_qboot == NULL) {
+        perror("Couldn't find krunfw_get_qboot symbol");
+        exit(-1);
+    }
+
+    SHA256_Init(&shactx);
+
+    payload_addr = krunfw_get_qboot(&payload_size);
+    printf("qboot: 0x%x, %lu\n", payload_addr, payload_size);
+    SHA256_Update(&shactx, payload_addr, payload_size);
+
+    payload_addr = krunfw_get_kernel(&load_addr, &payload_size);
+    printf("kernel: 0x%x, %lu\n", payload_addr, payload_size);
+    SHA256_Update(&shactx, payload_addr, payload_size);
+
+    payload_addr = krunfw_get_initrd(&payload_size);
+    printf("initrd: 0x%x, %lu\n", payload_addr, payload_size);
+    SHA256_Update(&shactx, payload_addr, payload_size);
+
+    SHA256_Final(&digest[0], &shactx);
+
+    for (i = 0; i < 32; ++i) {
+        printf("%02lx", digest[i] & 0xFFl);
+    }
+
+    printf("\n");
+
+    return 0;
+}