ipa: Name IPA modules after their source directory

The IPAModuleInfo::name field is currently a free-formed string that has
little use. Tighten its usage rules to make it suitable for building
file system paths to IPA-specific resources by matching the directory
name of the IPA module.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

src/ipa/rkisp1/rkisp1.cpp

@@ -274,7 +274,7 @@ const struct IPAModuleInfo ipaModuleInfo = {
 	IPA_MODULE_API_VERSION,
 	1,
 	"PipelineHandlerRkISP1",
-	"RkISP1 IPA",
+	"rkisp1",
 };
 
 struct ipa_context *ipaCreate()

src/ipa/vimc/vimc.cpp

@@ -126,7 +126,7 @@ const struct IPAModuleInfo ipaModuleInfo = {
 	IPA_MODULE_API_VERSION,
 	0,
 	"PipelineHandlerVimc",
-	"Dummy IPA for Vimc",
+	"vimc",
 };
 
 struct ipa_context *ipaCreate()

src/libcamera/ipa_module.cpp

@@ -9,6 +9,7 @@
 
 #include <algorithm>
 #include <array>
+#include <ctype.h>
 #include <dlfcn.h>
 #include <elf.h>
 #include <errno.h>
@@ -216,6 +217,11 @@ Span<uint8_t> elfLoadSymbol(Span<uint8_t> elf, const char *symbol)
  * \var IPAModuleInfo::name
  * \brief The name of the IPA module
  *
+ * The name may be used to build file system paths to IPA-specific resources.
+ * It shall only contain printable characters, and may not contain '/', '*',
+ * '?' or '\'. For IPA modules included in libcamera, it shall match the
+ * directory of the IPA module in the source tree.
+ *
  * \todo Allow user to choose to isolate open source IPAs
  */
 
@@ -287,6 +293,20 @@ int IPAModule::loadIPAModuleInfo()
 		return -EINVAL;
 	}
 
+	/* Validate the IPA module name. */
+	std::string ipaName = info_.name;
+	auto iter = std::find_if_not(ipaName.begin(), ipaName.end(),
+				     [](unsigned char c) -> bool {
+					     return isprint(c) && c != '/' &&
+						    c != '?' && c != '*' &&
+						    c != '\\';
+				     });
+	if (iter != ipaName.end()) {
+		LOG(IPAModule, Error)
+			<< "Invalid IPA module name '" << ipaName << "'";
+		return -EINVAL;
+	}
+
 	/* Load the signature. Failures are not fatal. */
 	File sign{ libPath_ + ".sign" };
 	if (!sign.open(File::ReadOnly)) {

test/ipa/ipa_module_test.cpp

@@ -58,7 +58,7 @@ protected:
 			IPA_MODULE_API_VERSION,
 			0,
 			"PipelineHandlerVimc",
-			"Dummy IPA for Vimc",
+			"vimc",
 		};
 
 		count += runTest("src/ipa/vimc/ipa_vimc.so", testInfo);