libmount (verity): plug libcryptsetup logger into our logging system

Allows logs from the library to be printed by our system:

731814: libmount:   VERITY: crypsetup: Device libmnt_img.raw already exists.

If the mount context is in verbose mode, enable all debug logs from
libcrypsetup as well.

Signed-off-by: Luca Boccassi <luca.boccassi@microsoft.com>

diff --git a/libmount/src/context_veritydev.c b/libmount/src/context_veritydev.c
index d66345603c09080ad8213de71a9df5c9c9bcea3f..af089e2a87f9bede5d8e6a029f46845dc0c438b7 100644 (file)
--- a/libmount/src/context_veritydev.c
+++ b/libmount/src/context_veritydev.c
@@ -37,6 +37,13 @@ static void *get_symbol(struct libmnt_context *cxt, void *dl, const char *name,
 }
 #endif
 
+static void libcryptsetup_log(int level __attribute__((__unused__)), const char *msg, void *data)
+{
+       struct libmnt_context *cxt = (struct libmnt_context *)data;
+
+       DBG(VERITY, ul_debugobj(cxt, "cryptsetup: %s", msg));
+}
+
 /* Taken from https://gitlab.com/cryptsetup/cryptsetup/blob/master/lib/utils_crypt.c#L225 */
 static size_t crypt_hex_to_bytes(const char *hex, char **result)
 {
@@ -81,6 +88,8 @@ int mnt_context_setup_veritydev(struct libmnt_context *cxt)
 #ifdef CRYPTSETUP_VIA_DLOPEN
        /* To avoid linking libmount to libcryptsetup, and keep the default dependencies list down, use dlopen */
        void *dl = NULL;
+       void (*sym_crypt_set_debug_level)(int) = NULL;
+       void (*sym_crypt_set_log_callback)(struct crypt_device *, void (*log)(int, const char *, void *), void *) = NULL;
        int (*sym_crypt_init_data_device)(struct crypt_device **, const char *, const char *) = NULL;
        int (*sym_crypt_load)(struct crypt_device *, const char *, void *) = NULL;
        int (*sym_crypt_get_volume_key_size)(struct crypt_device *) = NULL;
@@ -93,6 +102,8 @@ int mnt_context_setup_veritydev(struct libmnt_context *cxt)
        int (*sym_crypt_get_verity_info)(struct crypt_device *, struct crypt_params_verity *) = NULL;
        int (*sym_crypt_volume_key_get)(struct crypt_device *, int, char *, size_t *, const char *, size_t) = NULL;
 #else
+       void (*sym_crypt_set_debug_level)(int) = &crypt_set_debug_level;
+       void (*sym_crypt_set_log_callback)(struct crypt_device *, void (*log)(int, const char *, void *), void *) = &crypt_set_log_callback;
        int (*sym_crypt_init_data_device)(struct crypt_device **, const char *, const char *) = &crypt_init_data_device;
        int (*sym_crypt_load)(struct crypt_device *, const char *, void *) = &crypt_load;
        int (*sym_crypt_get_volume_key_size)(struct crypt_device *) = &crypt_get_volume_key_size;
@@ -254,6 +265,10 @@ int mnt_context_setup_veritydev(struct libmnt_context *cxt)
        /* clear errors first, then load all the libcryptsetup symbols */
        dlerror();
 
+       if (rc == 0)
+               *(void **)(&sym_crypt_set_debug_level) = get_symbol(cxt, dl, "crypt_set_debug_level", &rc);
+       if (rc == 0)
+               *(void **)(&sym_crypt_set_log_callback) = get_symbol(cxt, dl, "crypt_set_log_callback", &rc);
        if (rc == 0)
                *(void **)(&sym_crypt_init_data_device) = get_symbol(cxt, dl, "crypt_init_data_device", &rc);
        if (rc == 0)
@@ -278,6 +293,10 @@ int mnt_context_setup_veritydev(struct libmnt_context *cxt)
        if (rc)
                goto done;
 
+       if (mnt_context_is_verbose(cxt))
+               (*sym_crypt_set_debug_level)(CRYPT_DEBUG_ALL);
+       (*sym_crypt_set_log_callback)(NULL, libcryptsetup_log, cxt);
+
        rc = (*sym_crypt_init_data_device)(&crypt_dev, hash_device, backing_file);
        if (rc)
                goto done;
@@ -410,10 +429,14 @@ int mnt_context_deferred_delete_veritydev(struct libmnt_context *cxt)
 #ifdef RTLD_DEEPBIND
        dl_flags |= RTLD_DEEPBIND;
 #endif
+       void (*sym_crypt_set_debug_level)(int) = NULL;
+       void (*sym_crypt_set_log_callback)(struct crypt_device *, void (*log)(int, const char *, void *), void *) = NULL;
        int (*sym_crypt_init_by_name)(struct crypt_device **, const char *) = NULL;
        int (*sym_crypt_deactivate_by_name)(struct crypt_device *, const char *, uint32_t) = NULL;
        void (*sym_crypt_free)(struct crypt_device *) = NULL;
 #else
+       void (*sym_crypt_set_debug_level)(int) = &crypt_set_debug_level;
+       void (*sym_crypt_set_log_callback)(struct crypt_device *, void (*log)(int, const char *, void *), void *) = &crypt_set_log_callback;
        int (*sym_crypt_init_by_name)(struct crypt_device **, const char *) = &crypt_init_by_name;
        int (*sym_crypt_deactivate_by_name)(struct crypt_device *, const char *, uint32_t) = &crypt_deactivate_by_name;
        void (*sym_crypt_free)(struct crypt_device *) = &crypt_free;
@@ -440,6 +463,10 @@ int mnt_context_deferred_delete_veritydev(struct libmnt_context *cxt)
        /* clear errors first */
        dlerror();
 
+       if (!rc)
+               *(void **)(&sym_crypt_set_debug_level) = get_symbol(cxt, dl, "crypt_set_debug_level", &rc);
+       if (!rc)
+               *(void **)(&sym_crypt_set_log_callback) = get_symbol(cxt, dl, "crypt_set_log_callback", &rc);
        if (!rc)
                *(void **)(&sym_crypt_init_by_name) = get_symbol(cxt, dl, "crypt_init_by_name", &rc);
        if (!rc)
@@ -448,6 +475,9 @@ int mnt_context_deferred_delete_veritydev(struct libmnt_context *cxt)
                *(void **)(&sym_crypt_free) = get_symbol(cxt, dl, "crypt_free", &rc);
 #endif
        if (!rc) {
+               if (mnt_context_is_verbose(cxt))
+                       (*sym_crypt_set_debug_level)(CRYPT_DEBUG_ALL);
+               (*sym_crypt_set_log_callback)(NULL, libcryptsetup_log, cxt);
                rc = (*sym_crypt_init_by_name)(&crypt_dev, src);
                if (!rc) {
                        rc = (*sym_crypt_deactivate_by_name)(crypt_dev, src, flags);