diff --git a/include/psa/crypto.h b/include/psa/crypto.h
index 9165463..47241a6 100644
--- a/include/psa/crypto.h
+++ b/include/psa/crypto.h
@@ -965,6 +965,36 @@
 #define PSA_ALG_IS_RSA_OAEP(alg)                                \
     (((alg) & ~PSA_ALG_HASH_MASK) == PSA_ALG_RSA_OAEP_BASE)
 
+#define PSA_ALG_HKDF_BASE                       ((psa_algorithm_t)0x30000100)
+/** Macro to build an HKDF algorithm.
+ *
+ * For example, `PSA_ALG_HKDF(PSA_ALG_SHA256)` is HKDF using HMAC-SHA-256.
+ *
+ * \param hash_alg      A hash algorithm (\c PSA_ALG_XXX value such that
+ *                      #PSA_ALG_IS_HASH(\p hash_alg) is true).
+ *
+ * \return              The corresponding HKDF algorithm.
+ * \return              Unspecified if \p alg is not a supported
+ *                      hash algorithm.
+ */
+#define PSA_ALG_HKDF(hash_alg)                                  \
+    (PSA_ALG_HKDF_BASE | ((hash_alg) & PSA_ALG_HASH_MASK))
+/** Whether the specified algorithm is an HKDF algorithm.
+ *
+ * HKDF is a family of key derivation algorithms that are based on a hash
+ * function and the HMAC construction.
+ *
+ * \param alg An algorithm identifier (value of type #psa_algorithm_t).
+ *
+ * \return 1 if \c alg is an HKDF algorithm, 0 otherwise.
+ *         This macro may return either 0 or 1 if \c alg is not a supported
+ *         key derivation algorithm identifier.
+ */
+#define PSA_ALG_IS_HKDF(alg)                            \
+    (((alg) & ~PSA_ALG_HASH_MASK) == PSA_ALG_HKDF_BASE)
+#define PSA_ALG_HKDF_GET_HASH(hkdf_alg)                         \
+    (PSA_ALG_CATEGORY_HASH | ((hkdf_alg) & PSA_ALG_HASH_MASK))
+
 /**@}*/
 
 /** \defgroup key_management Key management
@@ -2638,6 +2668,8 @@
  * be used to produce keys and other cryptographic material.
  *
  * The role of \p label and \p salt is as follows:
+ * - For HKDF (#PSA_ALG_HKDF), \p salt is the salt used in the "extract" step
+ *   and \p label is the info string used in the "expand" step.
  *
  * \param[in,out] generator       The generator object to set up. It must
  *                                have been initialized to .
diff --git a/include/psa/crypto_struct.h b/include/psa/crypto_struct.h
index 27a9f1e..baf5b14 100644
--- a/include/psa/crypto_struct.h
+++ b/include/psa/crypto_struct.h
@@ -130,6 +130,20 @@
     } ctx;
 };
 
+typedef struct
+{
+    uint8_t *info;
+    size_t info_length;
+    psa_hmac_internal_data hmac;
+    uint8_t prk[PSA_HASH_MAX_SIZE];
+    uint8_t output_block[PSA_HASH_MAX_SIZE];
+#if PSA_HASH_MAX_SIZE > 0xff
+#error "PSA_HASH_MAX_SIZE does not fit in uint8_t"
+#endif
+    uint8_t offset_in_block;
+    uint8_t block_number;
+} psa_hkdf_generator_t;
+
 struct psa_crypto_generator_s
 {
     psa_algorithm_t alg;
@@ -141,6 +155,9 @@
             uint8_t *data;
             size_t size;
         } buffer;
+#if defined(MBEDTLS_MD_C)
+        psa_hkdf_generator_t hkdf;
+#endif
     } ctx;
 };