Add some more PE helpers we need for SBAT

Signed-off-by: Peter Jones <pjones@redhat.com>

pe.c

@@ -240,6 +240,60 @@ get_section_vma (UINTN section_num,
 	return EFI_SUCCESS;
 }
 
+EFI_STATUS
+get_section_vma_by_name (char *name, size_t namesz,
+			 char *buffer, size_t bufsz,
+			 PE_COFF_LOADER_IMAGE_CONTEXT *context,
+			 char **basep, size_t *sizep,
+			 EFI_IMAGE_SECTION_HEADER **sectionp)
+{
+	UINTN i;
+	char namebuf[9];
+
+	if (!name || namesz == 0 || !buffer || bufsz < namesz || !context
+	    || !basep || !sizep || !sectionp)
+		return EFI_INVALID_PARAMETER;
+
+	/*
+	 * This code currently is only used for ".reloc\0\0" and
+	 * ".sbat\0\0\0", and it doesn't know how to look up longer section
+	 * names.
+	 */
+	if (namesz > 8)
+		return EFI_UNSUPPORTED;
+
+	SetMem(namebuf, sizeof(namebuf), 0);
+	CopyMem(namebuf, name, MIN(namesz, 8));
+
+	/*
+	 * Copy the executable's sections to their desired offsets
+	 */
+	for (i = 0; i < context->NumberOfSections; i++) {
+		EFI_STATUS status;
+		EFI_IMAGE_SECTION_HEADER *section = NULL;
+		char *base = NULL;
+		size_t size = 0;
+
+		status = get_section_vma(i, buffer, bufsz, context, &base, &size, &section);
+		if (!EFI_ERROR(status)) {
+			if (CompareMem(section->Name, namebuf, 8) == 0) {
+				*basep = base;
+				*sizep = size;
+				*sectionp = section;
+				return EFI_SUCCESS;
+			}
+			continue;
+		}
+
+		switch(status) {
+		case EFI_NOT_FOUND:
+			break;
+		}
+	}
+
+	return EFI_NOT_FOUND;
+}
+
 /*
  * Calculate the SHA1 and SHA256 hashes of a binary
  */