+/*
+ * At present we only support signing on the host, and verification on the
+ * device
+ */
+#if defined(CONFIG_FIT_SIGNATURE)
+# ifdef USE_HOSTCC
+# define IMAGE_ENABLE_SIGN 1
+# define IMAGE_ENABLE_VERIFY 0
+#else
+# define IMAGE_ENABLE_SIGN 0
+# define IMAGE_ENABLE_VERIFY 1
+# endif
+#else
+# define IMAGE_ENABLE_SIGN 0
+# define IMAGE_ENABLE_VERIFY 0
+#endif
+
+#ifdef USE_HOSTCC
+# define gd_fdt_blob() NULL
+#else
+# define gd_fdt_blob() (gd->fdt_blob)
+#endif
+
+#ifdef CONFIG_FIT_BEST_MATCH
+#define IMAGE_ENABLE_BEST_MATCH 1
+#else
+#define IMAGE_ENABLE_BEST_MATCH 0
+#endif
+
+/* Information passed to the signing routines */
+struct image_sign_info {
+ const char *keydir; /* Directory conaining keys */
+ const char *keyname; /* Name of key to use */
+ void *fit; /* Pointer to FIT blob */
+ int node_offset; /* Offset of signature node */
+ struct image_sig_algo *algo; /* Algorithm information */
+ const void *fdt_blob; /* FDT containing public keys */
+ int required_keynode; /* Node offset of key to use: -1=any */
+ const char *require_keys; /* Value for 'required' property */
+};
+
+/* A part of an image, used for hashing */
+struct image_region {
+ const void *data;
+ int size;
+};
+
+struct image_sig_algo {
+ const char *name; /* Name of algorithm */
+
+ /**
+ * sign() - calculate and return signature for given input data
+ *
+ * @info: Specifies key and FIT information
+ * @data: Pointer to the input data
+ * @data_len: Data length
+ * @sigp: Set to an allocated buffer holding the signature
+ * @sig_len: Set to length of the calculated hash
+ *
+ * This computes input data signature according to selected algorithm.
+ * Resulting signature value is placed in an allocated buffer, the
+ * pointer is returned as *sigp. The length of the calculated
+ * signature is returned via the sig_len pointer argument. The caller
+ * should free *sigp.
+ *
+ * @return: 0, on success, -ve on error
+ */
+ int (*sign)(struct image_sign_info *info,
+ const struct image_region region[],
+ int region_count, uint8_t **sigp, uint *sig_len);
+
+ /**
+ * add_verify_data() - Add verification information to FDT
+ *
+ * Add public key information to the FDT node, suitable for
+ * verification at run-time. The information added depends on the
+ * algorithm being used.
+ *
+ * @info: Specifies key and FIT information
+ * @keydest: Destination FDT blob for public key data
+ * @return: 0, on success, -ve on error
+ */
+ int (*add_verify_data)(struct image_sign_info *info, void *keydest);
+
+ /**
+ * verify() - Verify a signature against some data
+ *
+ * @info: Specifies key and FIT information
+ * @data: Pointer to the input data
+ * @data_len: Data length
+ * @sig: Signature
+ * @sig_len: Number of bytes in signature
+ * @return 0 if verified, -ve on error
+ */
+ int (*verify)(struct image_sign_info *info,
+ const struct image_region region[], int region_count,
+ uint8_t *sig, uint sig_len);
+};
+
+/**
+ * image_get_sig_algo() - Look up a signature algortihm
+ *
+ * @param name Name of algorithm
+ * @return pointer to algorithm information, or NULL if not found
+ */
+struct image_sig_algo *image_get_sig_algo(const char *name);
+
+/**
+ * fit_image_verify_required_sigs() - Verify signatures marked as 'required'
+ *
+ * @fit: FIT to check
+ * @image_noffset: Offset of image node to check
+ * @data: Image data to check
+ * @size: Size of image data
+ * @sig_blob: FDT containing public keys
+ * @no_sigsp: Returns 1 if no signatures were required, and
+ * therefore nothing was checked. The caller may wish
+ * to fall back to other mechanisms, or refuse to
+ * boot.
+ * @return 0 if all verified ok, <0 on error
+ */
+int fit_image_verify_required_sigs(const void *fit, int image_noffset,
+ const char *data, size_t size, const void *sig_blob,
+ int *no_sigsp);
+
+/**
+ * fit_image_check_sig() - Check a single image signature node
+ *
+ * @fit: FIT to check
+ * @noffset: Offset of signature node to check
+ * @data: Image data to check
+ * @size: Size of image data
+ * @required_keynode: Offset in the control FDT of the required key node,
+ * if any. If this is given, then the image wil not
+ * pass verification unless that key is used. If this is
+ * -1 then any signature will do.
+ * @err_msgp: In the event of an error, this will be pointed to a
+ * help error string to display to the user.
+ * @return 0 if all verified ok, <0 on error
+ */
+int fit_image_check_sig(const void *fit, int noffset, const void *data,
+ size_t size, int required_keynode, char **err_msgp);
+
+/**
+ * fit_region_make_list() - Make a list of regions to hash
+ *
+ * Given a list of FIT regions (offset, size) provided by libfdt, create
+ * a list of regions (void *, size) for use by the signature creationg
+ * and verification code.
+ *
+ * @fit: FIT image to process
+ * @fdt_regions: Regions as returned by libfdt
+ * @count: Number of regions returned by libfdt
+ * @region: Place to put list of regions (NULL to allocate it)
+ * @return pointer to list of regions, or NULL if out of memory
+ */
+struct image_region *fit_region_make_list(const void *fit,
+ struct fdt_region *fdt_regions, int count,
+ struct image_region *region);
+