load security code from install directory

This allows us the compiled saturn-mkboot to be distributed, as it's
no longer linked against the security code binary, but rather loads it
at runtime.

1 files changed, 33 insertions, 27 deletions

diff --git a/src/saturn-mkboot.c b/src/saturn-mkboot.c
index 43e1a85..7551059 100644
--- a/src/saturn-mkboot.c
+++ b/src/saturn-mkboot.c
@@ -27,7 +27,7 @@ static struct systemid sysid = {
 	.load_size    = 0,
 };
 
-static char ipbuf[0x7200];
+static char ipbuf[0x7f00];
 static char *ipfile, *outfile;
 
 static void serialize_region_code(char *out, const struct symbolname *region)
@@ -45,9 +45,6 @@ static void serialize_region_code(char *out, const struct symbolname *region)
 
 static int write_output(FILE *fp)
 {
-	extern const unsigned char securitycode[];
-	extern const size_t        securitycode_size;
-
 	/* system id - 0x100 bytes */
 	WRITE  (fp, &sysid, offsetof(struct systemid, bootsize));
 	WRITE32(fp, sysid.bootsize);
@@ -59,11 +56,8 @@ static int write_output(FILE *fp)
 	WRITE32(fp, 0); /* reserved bytes */
 	WRITE32(fp, 0); /* reserved bytes */
 
-	/* security code */
-	WRITE(fp, securitycode, securitycode_size);
-
 	/* initial program */
-	WRITE(fp, ipbuf, sysid.bootsize - 0xe00);
+	WRITE(fp, ipbuf, sysid.bootsize - 0x100);
 	return ferror(fp) ? -1 : 0;
 }
 
@@ -84,34 +78,43 @@ static FILE *open_boot_file(const char *filename)
 	return NULL;
 }
 
+static size_t readfile(FILE *fp, char *out, size_t maxsize, const char *errprefix)
+{
+	size_t size = fread(out, 1, maxsize, fp);
+	if (size == maxsize && fgetc(fp) != EOF) {
+		fprintf(stderr, "%s: exceeds maximum size\n", errprefix);
+		size = -1;
+	}
+	return size;
+}
+
+static size_t load_security_code(char *out)
+{
+	const char *errprefix = "Error loading security code";
+	FILE *fp;
+	if (!(fp = fopen(DATA_PATH "/securitycode.bin", "rb"))) {
+		perror(errprefix);
+		return -1;
+	}
+	size_t size = readfile(fp, out, 0xd00, errprefix);
+	if (size != -1 && size != 0xd00) fprintf(stderr, "%s: wrong size\n", errprefix);
+	fclose(fp);
+	return size;
+}
+
 static size_t load_ip(char *out, size_t maxsize)
 {
-	size_t size;
 	FILE *fp = ipfile ? open_boot_file(ipfile) : open_installed_boot_file("simple");
 	const char *errprefix = "Error loading initial program";
 
-	if (!fp) goto fail_perror;
-	if ((size = fread(out, 1, maxsize, fp)) < maxsize) {
-		/* read fewer than requested amount. determine if we hit error or eof */
-		if (ferror(fp)) {
-			goto fail_perror;
-		}
-	} else {
-		/* successfully read the requested amount. verify we reached eof */
-		if (fgetc(fp) != EOF) {
-			fprintf(stderr, "%s: exceeds maximum size\n", errprefix);
-			goto fail;
-		}
+	if (!fp) {
+		perror(errprefix);
+		return -1;
 	}
 
+	size_t size = readfile(fp, out, maxsize, errprefix);
 	fclose(fp);
 	return size;
-
-fail_perror:
-	perror(errprefix);
-fail:
-	if (fp) fclose(fp);
-	return -1;
 }
 
 static void print_symbols(int width, const struct symbolname *symbols)
@@ -248,6 +251,9 @@ int main(int argc, char **argv)
 		sysid.bootsize += 32;
 	}
 
+	ipsize = load_security_code(ipout);
+	if (ipsize == -1) goto fail;
+	ipout += ipsize;
 	ipsize = load_ip(ipout, sizeof ipbuf - (ipout - ipbuf));
 	if (ipsize == -1) goto fail;
 	sysid.bootsize += ipsize;