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Diffstat (limited to 'include/mbedtls/pk.h')
| -rw-r--r-- | include/mbedtls/pk.h | 1288 |
1 files changed, 1288 insertions, 0 deletions
diff --git a/include/mbedtls/pk.h b/include/mbedtls/pk.h new file mode 100644 index 00000000000..fde302f8720 --- /dev/null +++ b/include/mbedtls/pk.h @@ -0,0 +1,1288 @@ +/** + * \file pk.h + * + * \brief Public Key abstraction layer + */ +/* + * Copyright The Mbed TLS Contributors + * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later + */ + +#ifndef MBEDTLS_PK_H +#define MBEDTLS_PK_H +#include "mbedtls/private_access.h" + +#include "mbedtls/build_info.h" + +#include "mbedtls/md.h" + +#if defined(MBEDTLS_RSA_C) +#include "mbedtls/rsa.h" +#endif + +#if defined(MBEDTLS_ECP_C) +#include "mbedtls/ecp.h" +#endif + +#if defined(MBEDTLS_ECDSA_C) +#include "mbedtls/ecdsa.h" +#endif + +#if defined(MBEDTLS_PSA_CRYPTO_CLIENT) +#include "psa/crypto.h" +#endif + +/** Memory allocation failed. */ +#define MBEDTLS_ERR_PK_ALLOC_FAILED -0x3F80 +/** Type mismatch, eg attempt to encrypt with an ECDSA key */ +#define MBEDTLS_ERR_PK_TYPE_MISMATCH -0x3F00 +/** Bad input parameters to function. */ +#define MBEDTLS_ERR_PK_BAD_INPUT_DATA -0x3E80 +/** Read/write of file failed. */ +#define MBEDTLS_ERR_PK_FILE_IO_ERROR -0x3E00 +/** Unsupported key version */ +#define MBEDTLS_ERR_PK_KEY_INVALID_VERSION -0x3D80 +/** Invalid key tag or value. */ +#define MBEDTLS_ERR_PK_KEY_INVALID_FORMAT -0x3D00 +/** Key algorithm is unsupported (only RSA and EC are supported). */ +#define MBEDTLS_ERR_PK_UNKNOWN_PK_ALG -0x3C80 +/** Private key password can't be empty. */ +#define MBEDTLS_ERR_PK_PASSWORD_REQUIRED -0x3C00 +/** Given private key password does not allow for correct decryption. */ +#define MBEDTLS_ERR_PK_PASSWORD_MISMATCH -0x3B80 +/** The pubkey tag or value is invalid (only RSA and EC are supported). */ +#define MBEDTLS_ERR_PK_INVALID_PUBKEY -0x3B00 +/** The algorithm tag or value is invalid. */ +#define MBEDTLS_ERR_PK_INVALID_ALG -0x3A80 +/** Elliptic curve is unsupported (only NIST curves are supported). */ +#define MBEDTLS_ERR_PK_UNKNOWN_NAMED_CURVE -0x3A00 +/** Unavailable feature, e.g. RSA disabled for RSA key. */ +#define MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE -0x3980 +/** The buffer contains a valid signature followed by more data. */ +#define MBEDTLS_ERR_PK_SIG_LEN_MISMATCH -0x3900 +/** The output buffer is too small. */ +#define MBEDTLS_ERR_PK_BUFFER_TOO_SMALL -0x3880 + +#ifdef __cplusplus +extern "C" { +#endif + +/** + * \brief Public key types + */ +typedef enum { + MBEDTLS_PK_NONE=0, + MBEDTLS_PK_RSA, + MBEDTLS_PK_ECKEY, + MBEDTLS_PK_ECKEY_DH, + MBEDTLS_PK_ECDSA, + MBEDTLS_PK_RSA_ALT, + MBEDTLS_PK_RSASSA_PSS, + MBEDTLS_PK_OPAQUE, +} mbedtls_pk_type_t; + +/** + * \brief Options for RSASSA-PSS signature verification. + * See \c mbedtls_rsa_rsassa_pss_verify_ext() + */ +typedef struct mbedtls_pk_rsassa_pss_options { + /** The digest to use for MGF1 in PSS. + * + * \note When #MBEDTLS_USE_PSA_CRYPTO is enabled and #MBEDTLS_RSA_C is + * disabled, this must be equal to the \c md_alg argument passed + * to mbedtls_pk_verify_ext(). In a future version of the library, + * this constraint may apply whenever #MBEDTLS_USE_PSA_CRYPTO is + * enabled regardless of the status of #MBEDTLS_RSA_C. + */ + mbedtls_md_type_t mgf1_hash_id; + + /** The expected length of the salt, in bytes. This may be + * #MBEDTLS_RSA_SALT_LEN_ANY to accept any salt length. + * + * \note When #MBEDTLS_USE_PSA_CRYPTO is enabled, only + * #MBEDTLS_RSA_SALT_LEN_ANY is valid. Any other value may be + * ignored (allowing any salt length). + */ + int expected_salt_len; + +} mbedtls_pk_rsassa_pss_options; + +/** + * \brief Maximum size of a signature made by mbedtls_pk_sign(). + */ +/* We need to set MBEDTLS_PK_SIGNATURE_MAX_SIZE to the maximum signature + * size among the supported signature types. Do it by starting at 0, + * then incrementally increasing to be large enough for each supported + * signature mechanism. + * + * The resulting value can be 0, for example if MBEDTLS_ECDH_C is enabled + * (which allows the pk module to be included) but neither MBEDTLS_ECDSA_C + * nor MBEDTLS_RSA_C nor any opaque signature mechanism (PSA or RSA_ALT). + */ +#define MBEDTLS_PK_SIGNATURE_MAX_SIZE 0 + +#if (defined(MBEDTLS_RSA_C) || defined(MBEDTLS_PK_RSA_ALT_SUPPORT)) && \ + MBEDTLS_MPI_MAX_SIZE > MBEDTLS_PK_SIGNATURE_MAX_SIZE +/* For RSA, the signature can be as large as the bignum module allows. + * For RSA_ALT, the signature size is not necessarily tied to what the + * bignum module can do, but in the absence of any specific setting, + * we use that (rsa_alt_sign_wrap in library/pk_wrap.h will check). */ +#undef MBEDTLS_PK_SIGNATURE_MAX_SIZE +#define MBEDTLS_PK_SIGNATURE_MAX_SIZE MBEDTLS_MPI_MAX_SIZE +#endif + +#if defined(MBEDTLS_ECDSA_C) && \ + MBEDTLS_ECDSA_MAX_LEN > MBEDTLS_PK_SIGNATURE_MAX_SIZE +/* For ECDSA, the ecdsa module exports a constant for the maximum + * signature size. */ +#undef MBEDTLS_PK_SIGNATURE_MAX_SIZE +#define MBEDTLS_PK_SIGNATURE_MAX_SIZE MBEDTLS_ECDSA_MAX_LEN +#endif + +#if defined(MBEDTLS_USE_PSA_CRYPTO) +#if PSA_SIGNATURE_MAX_SIZE > MBEDTLS_PK_SIGNATURE_MAX_SIZE +/* PSA_SIGNATURE_MAX_SIZE is the maximum size of a signature made + * through the PSA API in the PSA representation. */ +#undef MBEDTLS_PK_SIGNATURE_MAX_SIZE +#define MBEDTLS_PK_SIGNATURE_MAX_SIZE PSA_SIGNATURE_MAX_SIZE +#endif + +#if PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE + 11 > MBEDTLS_PK_SIGNATURE_MAX_SIZE +/* The Mbed TLS representation is different for ECDSA signatures: + * PSA uses the raw concatenation of r and s, + * whereas Mbed TLS uses the ASN.1 representation (SEQUENCE of two INTEGERs). + * Add the overhead of ASN.1: up to (1+2) + 2 * (1+2+1) for the + * types, lengths (represented by up to 2 bytes), and potential leading + * zeros of the INTEGERs and the SEQUENCE. */ +#undef MBEDTLS_PK_SIGNATURE_MAX_SIZE +#define MBEDTLS_PK_SIGNATURE_MAX_SIZE (PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE + 11) +#endif +#endif /* defined(MBEDTLS_USE_PSA_CRYPTO) */ + +/* Internal helper to define which fields in the pk_context structure below + * should be used for EC keys: legacy ecp_keypair or the raw (PSA friendly) + * format. It should be noted that this only affects how data is stored, not + * which functions are used for various operations. The overall picture looks + * like this: + * - if USE_PSA is not defined and ECP_C is defined then use ecp_keypair data + * structure and legacy functions + * - if USE_PSA is defined and + * - if ECP_C then use ecp_keypair structure, convert data to a PSA friendly + * format and use PSA functions + * - if !ECP_C then use new raw data and PSA functions directly. + * + * The main reason for the "intermediate" (USE_PSA + ECP_C) above is that as long + * as ECP_C is defined mbedtls_pk_ec() gives the user a read/write access to the + * ecp_keypair structure inside the pk_context so they can modify it using + * ECP functions which are not under PK module's control. + */ +#if defined(MBEDTLS_USE_PSA_CRYPTO) && defined(PSA_WANT_KEY_TYPE_ECC_PUBLIC_KEY) && \ + !defined(MBEDTLS_ECP_C) +#define MBEDTLS_PK_USE_PSA_EC_DATA +#endif + +/** + * \brief Types for interfacing with the debug module + */ +typedef enum { + MBEDTLS_PK_DEBUG_NONE = 0, + MBEDTLS_PK_DEBUG_MPI, + MBEDTLS_PK_DEBUG_ECP, + MBEDTLS_PK_DEBUG_PSA_EC, +} mbedtls_pk_debug_type; + +/** + * \brief Item to send to the debug module + */ +typedef struct mbedtls_pk_debug_item { + mbedtls_pk_debug_type MBEDTLS_PRIVATE(type); + const char *MBEDTLS_PRIVATE(name); + void *MBEDTLS_PRIVATE(value); +} mbedtls_pk_debug_item; + +/** Maximum number of item send for debugging, plus 1 */ +#define MBEDTLS_PK_DEBUG_MAX_ITEMS 3 + +/** + * \brief Public key information and operations + * + * \note The library does not support custom pk info structures, + * only built-in structures returned by + * mbedtls_cipher_info_from_type(). + */ +typedef struct mbedtls_pk_info_t mbedtls_pk_info_t; + +#define MBEDTLS_PK_MAX_EC_PUBKEY_RAW_LEN \ + PSA_KEY_EXPORT_ECC_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS) +/** + * \brief Public key container + */ +typedef struct mbedtls_pk_context { + const mbedtls_pk_info_t *MBEDTLS_PRIVATE(pk_info); /**< Public key information */ + void *MBEDTLS_PRIVATE(pk_ctx); /**< Underlying public key context */ + /* The following field is used to store the ID of a private key in the + * following cases: + * - opaque key when MBEDTLS_USE_PSA_CRYPTO is defined + * - normal key when MBEDTLS_PK_USE_PSA_EC_DATA is defined. In this case: + * - the pk_ctx above is not not used to store the private key anymore. + * Actually that field not populated at all in this case because also + * the public key will be stored in raw format as explained below + * - this ID is used for all private key operations (ex: sign, check + * key pair, key write, etc) using PSA functions + * + * Note: this private key storing solution only affects EC keys, not the + * other ones. The latters still use the pk_ctx to store their own + * context. */ +#if defined(MBEDTLS_USE_PSA_CRYPTO) + mbedtls_svc_key_id_t MBEDTLS_PRIVATE(priv_id); /**< Key ID for opaque keys */ +#endif /* MBEDTLS_USE_PSA_CRYPTO */ + /* The following fields are meant for storing the public key in raw format + * which is handy for: + * - easily importing it into the PSA context + * - reducing the ECP module dependencies in the PK one. + * + * When MBEDTLS_PK_USE_PSA_EC_DATA is enabled: + * - the pk_ctx above is not used anymore for storing the public key + * inside the ecp_keypair structure + * - the following fields are used for all public key operations: signature + * verify, key pair check and key write. + * - For a key pair, priv_id contains the private key. For a public key, + * priv_id is null. + * Of course, when MBEDTLS_PK_USE_PSA_EC_DATA is not enabled, the legacy + * ecp_keypair structure is used for storing the public key and performing + * all the operations. + * + * Note: This new public key storing solution only works for EC keys, not + * other ones. The latters still use pk_ctx to store their own + * context. + */ +#if defined(MBEDTLS_PK_USE_PSA_EC_DATA) + uint8_t MBEDTLS_PRIVATE(pub_raw)[MBEDTLS_PK_MAX_EC_PUBKEY_RAW_LEN]; /**< Raw public key */ + size_t MBEDTLS_PRIVATE(pub_raw_len); /**< Valid bytes in "pub_raw" */ + psa_ecc_family_t MBEDTLS_PRIVATE(ec_family); /**< EC family of pk */ + size_t MBEDTLS_PRIVATE(ec_bits); /**< Curve's bits of pk */ +#endif /* MBEDTLS_PK_USE_PSA_EC_DATA */ +} mbedtls_pk_context; + +#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE) +/** + * \brief Context for resuming operations + */ +typedef struct { + const mbedtls_pk_info_t *MBEDTLS_PRIVATE(pk_info); /**< Public key information */ + void *MBEDTLS_PRIVATE(rs_ctx); /**< Underlying restart context */ +} mbedtls_pk_restart_ctx; +#else /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */ +/* Now we can declare functions that take a pointer to that */ +typedef void mbedtls_pk_restart_ctx; +#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */ + +#if defined(MBEDTLS_PK_RSA_ALT_SUPPORT) +/** + * \brief Types for RSA-alt abstraction + */ +typedef int (*mbedtls_pk_rsa_alt_decrypt_func)(void *ctx, size_t *olen, + const unsigned char *input, unsigned char *output, + size_t output_max_len); +typedef int (*mbedtls_pk_rsa_alt_sign_func)(void *ctx, + int (*f_rng)(void *, unsigned char *, size_t), + void *p_rng, + mbedtls_md_type_t md_alg, unsigned int hashlen, + const unsigned char *hash, unsigned char *sig); +typedef size_t (*mbedtls_pk_rsa_alt_key_len_func)(void *ctx); +#endif /* MBEDTLS_PK_RSA_ALT_SUPPORT */ + +/** + * \brief Return information associated with the given PK type + * + * \param pk_type PK type to search for. + * + * \return The PK info associated with the type or NULL if not found. + */ +const mbedtls_pk_info_t *mbedtls_pk_info_from_type(mbedtls_pk_type_t pk_type); + +/** + * \brief Initialize a #mbedtls_pk_context (as NONE). + * + * \param ctx The context to initialize. + * This must not be \c NULL. + */ +void mbedtls_pk_init(mbedtls_pk_context *ctx); + +/** + * \brief Free the components of a #mbedtls_pk_context. + * + * \param ctx The context to clear. It must have been initialized. + * If this is \c NULL, this function does nothing. + * + * \note For contexts that have been set up with + * mbedtls_pk_setup_opaque(), this does not free the underlying + * PSA key and you still need to call psa_destroy_key() + * independently if you want to destroy that key. + */ +void mbedtls_pk_free(mbedtls_pk_context *ctx); + +#if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE) +/** + * \brief Initialize a restart context + * + * \param ctx The context to initialize. + * This must not be \c NULL. + */ +void mbedtls_pk_restart_init(mbedtls_pk_restart_ctx *ctx); + +/** + * \brief Free the components of a restart context + * + * \param ctx The context to clear. It must have been initialized. + * If this is \c NULL, this function does nothing. + */ +void mbedtls_pk_restart_free(mbedtls_pk_restart_ctx *ctx); +#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */ + +/** + * \brief Initialize a PK context with the information given + * and allocates the type-specific PK subcontext. + * + * \param ctx Context to initialize. It must not have been set + * up yet (type #MBEDTLS_PK_NONE). + * \param info Information to use + * + * \return 0 on success, + * MBEDTLS_ERR_PK_BAD_INPUT_DATA on invalid input, + * MBEDTLS_ERR_PK_ALLOC_FAILED on allocation failure. + * + * \note For contexts holding an RSA-alt key, use + * \c mbedtls_pk_setup_rsa_alt() instead. + */ +int mbedtls_pk_setup(mbedtls_pk_context *ctx, const mbedtls_pk_info_t *info); + +#if defined(MBEDTLS_USE_PSA_CRYPTO) +/** + * \brief Initialize a PK context to wrap a PSA key. + * + * \note This function replaces mbedtls_pk_setup() for contexts + * that wrap a (possibly opaque) PSA key instead of + * storing and manipulating the key material directly. + * + * \param ctx The context to initialize. It must be empty (type NONE). + * \param key The PSA key to wrap, which must hold an ECC or RSA key + * pair (see notes below). + * + * \note The wrapped key must remain valid as long as the + * wrapping PK context is in use, that is at least between + * the point this function is called and the point + * mbedtls_pk_free() is called on this context. The wrapped + * key might then be independently used or destroyed. + * + * \note This function is currently only available for ECC or RSA + * key pairs (that is, keys containing private key material). + * Support for other key types may be added later. + * + * \return \c 0 on success. + * \return #MBEDTLS_ERR_PK_BAD_INPUT_DATA on invalid input + * (context already used, invalid key identifier). + * \return #MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE if the key is not an + * ECC key pair. + * \return #MBEDTLS_ERR_PK_ALLOC_FAILED on allocation failure. + */ +int mbedtls_pk_setup_opaque(mbedtls_pk_context *ctx, + const mbedtls_svc_key_id_t key); +#endif /* MBEDTLS_USE_PSA_CRYPTO */ + +#if defined(MBEDTLS_PK_RSA_ALT_SUPPORT) +/** + * \brief Initialize an RSA-alt context + * + * \param ctx Context to initialize. It must not have been set + * up yet (type #MBEDTLS_PK_NONE). + * \param key RSA key pointer + * \param decrypt_func Decryption function + * \param sign_func Signing function + * \param key_len_func Function returning key length in bytes + * + * \return 0 on success, or MBEDTLS_ERR_PK_BAD_INPUT_DATA if the + * context wasn't already initialized as RSA_ALT. + * + * \note This function replaces \c mbedtls_pk_setup() for RSA-alt. + */ +int mbedtls_pk_setup_rsa_alt(mbedtls_pk_context *ctx, void *key, + mbedtls_pk_rsa_alt_decrypt_func decrypt_func, + mbedtls_pk_rsa_alt_sign_func sign_func, + mbedtls_pk_rsa_alt_key_len_func key_len_func); +#endif /* MBEDTLS_PK_RSA_ALT_SUPPORT */ + +/** + * \brief Get the size in bits of the underlying key + * + * \param ctx The context to query. It must have been initialized. + * + * \return Key size in bits, or 0 on error + */ +size_t mbedtls_pk_get_bitlen(const mbedtls_pk_context *ctx); + +/** + * \brief Get the length in bytes of the underlying key + * + * \param ctx The context to query. It must have been initialized. + * + * \return Key length in bytes, or 0 on error + */ +static inline size_t mbedtls_pk_get_len(const mbedtls_pk_context *ctx) +{ + return (mbedtls_pk_get_bitlen(ctx) + 7) / 8; +} + +/** + * \brief Tell if a context can do the operation given by type + * + * \param ctx The context to query. It must have been initialized. + * \param type The desired type. + * + * \return 1 if the context can do operations on the given type. + * \return 0 if the context cannot do the operations on the given + * type. This is always the case for a context that has + * been initialized but not set up, or that has been + * cleared with mbedtls_pk_free(). + */ +int mbedtls_pk_can_do(const mbedtls_pk_context *ctx, mbedtls_pk_type_t type); + +#if defined(MBEDTLS_USE_PSA_CRYPTO) +/** + * \brief Tell if context can do the operation given by PSA algorithm + * + * \param ctx The context to query. It must have been initialized. + * \param alg PSA algorithm to check against, the following are allowed: + * PSA_ALG_RSA_PKCS1V15_SIGN(hash), + * PSA_ALG_RSA_PSS(hash), + * PSA_ALG_RSA_PKCS1V15_CRYPT, + * PSA_ALG_ECDSA(hash), + * PSA_ALG_ECDH, where hash is a specific hash. + * \param usage PSA usage flag to check against, must be composed of: + * PSA_KEY_USAGE_SIGN_HASH + * PSA_KEY_USAGE_DECRYPT + * PSA_KEY_USAGE_DERIVE. + * Context key must match all passed usage flags. + * + * \warning Since the set of allowed algorithms and usage flags may be + * expanded in the future, the return value \c 0 should not + * be taken in account for non-allowed algorithms and usage + * flags. + * + * \return 1 if the context can do operations on the given type. + * \return 0 if the context cannot do the operations on the given + * type, for non-allowed algorithms and usage flags, or + * for a context that has been initialized but not set up + * or that has been cleared with mbedtls_pk_free(). + */ +int mbedtls_pk_can_do_ext(const mbedtls_pk_context *ctx, psa_algorithm_t alg, + psa_key_usage_t usage); +#endif /* MBEDTLS_USE_PSA_CRYPTO */ + +#if defined(MBEDTLS_PSA_CRYPTO_CLIENT) +/** + * \brief Determine valid PSA attributes that can be used to + * import a key into PSA. + * + * The attributes determined by this function are suitable + * for calling mbedtls_pk_import_into_psa() to create + * a PSA key with the same key material. + * + * The typical flow of operations involving this function is + * ``` + * psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT; + * int ret = mbedtls_pk_get_psa_attributes(pk, &attributes); + * if (ret != 0) ...; // error handling omitted + * // Tweak attributes if desired + * psa_key_id_t key_id = 0; + * ret = mbedtls_pk_import_into_psa(pk, &attributes, &key_id); + * if (ret != 0) ...; // error handling omitted + * ``` + * + * \note This function does not support RSA-alt contexts + * (set up with mbedtls_pk_setup_rsa_alt()). + * + * \param[in] pk The PK context to use. It must have been set up. + * It can either contain a key pair or just a public key. + * \param usage A single `PSA_KEY_USAGE_xxx` flag among the following: + * - #PSA_KEY_USAGE_DECRYPT: \p pk must contain a + * key pair. The output \p attributes will contain a + * key pair type, and the usage policy will allow + * #PSA_KEY_USAGE_ENCRYPT as well as + * #PSA_KEY_USAGE_DECRYPT. + * - #PSA_KEY_USAGE_DERIVE: \p pk must contain a + * key pair. The output \p attributes will contain a + * key pair type. + * - #PSA_KEY_USAGE_ENCRYPT: The output + * \p attributes will contain a public key type. + * - #PSA_KEY_USAGE_SIGN_HASH: \p pk must contain a + * key pair. The output \p attributes will contain a + * key pair type, and the usage policy will allow + * #PSA_KEY_USAGE_VERIFY_HASH as well as + * #PSA_KEY_USAGE_SIGN_HASH. + * - #PSA_KEY_USAGE_SIGN_MESSAGE: \p pk must contain a + * key pair. The output \p attributes will contain a + * key pair type, and the usage policy will allow + * #PSA_KEY_USAGE_VERIFY_MESSAGE as well as + * #PSA_KEY_USAGE_SIGN_MESSAGE. + * - #PSA_KEY_USAGE_VERIFY_HASH: The output + * \p attributes will contain a public key type. + * - #PSA_KEY_USAGE_VERIFY_MESSAGE: The output + * \p attributes will contain a public key type. + * \param[out] attributes + * On success, valid attributes to import the key into PSA. + * - The lifetime and key identifier are unchanged. If the + * attribute structure was initialized or reset before + * calling this function, this will result in a volatile + * key. Call psa_set_key_identifier() before or after this + * function if you wish to create a persistent key. Call + * psa_set_key_lifetime() before or after this function if + * you wish to import the key in a secure element. + * - The key type and bit-size are determined by the contents + * of the PK context. If the PK context contains a key + * pair, the key type can be either a key pair type or + * the corresponding public key type, depending on + * \p usage. If the PK context contains a public key, + * the key type is a public key type. + * - The key's policy is determined by the key type and + * the \p usage parameter. The usage always allows + * \p usage, exporting and copying the key, and + * possibly other permissions as documented for the + * \p usage parameter. + * The permitted algorithm policy is determined as follows + * based on the #mbedtls_pk_type_t type of \p pk, + * the chosen \p usage and other factors: + * - #MBEDTLS_PK_RSA whose underlying + * #mbedtls_rsa_context has the padding mode + * #MBEDTLS_RSA_PKCS_V15: + * #PSA_ALG_RSA_PKCS1V15_SIGN(#PSA_ALG_ANY_HASH) + * if \p usage is SIGN/VERIFY, and + * #PSA_ALG_RSA_PKCS1V15_CRYPT + * if \p usage is ENCRYPT/DECRYPT. + * - #MBEDTLS_PK_RSA whose underlying + * #mbedtls_rsa_context has the padding mode + * #MBEDTLS_RSA_PKCS_V21 and the digest type + * corresponding to the PSA algorithm \c hash: + * #PSA_ALG_RSA_PSS_ANY_SALT(#PSA_ALG_ANY_HASH) + * if \p usage is SIGN/VERIFY, and + * #PSA_ALG_RSA_OAEP(\c hash) + * if \p usage is ENCRYPT/DECRYPT. + * - #MBEDTLS_PK_RSA_ALT: not supported. + * - #MBEDTLS_PK_ECDSA or #MBEDTLS_PK_ECKEY + * if \p usage is SIGN/VERIFY: + * #PSA_ALG_DETERMINISTIC_ECDSA(#PSA_ALG_ANY_HASH) + * if #MBEDTLS_ECDSA_DETERMINISTIC is enabled, + * otherwise #PSA_ALG_ECDSA(#PSA_ALG_ANY_HASH). + * - #MBEDTLS_PK_ECKEY_DH or #MBEDTLS_PK_ECKEY + * if \p usage is DERIVE: + * #PSA_ALG_ECDH. + * - #MBEDTLS_PK_OPAQUE: same as the primary algorithm + * set for the underlying PSA key, except that + * sign/decrypt flags are removed if the type is + * set to a public key type. + * The underlying key must allow \p usage. + * Note that the enrollment algorithm set with + * psa_set_key_enrollment_algorithm() is not copied. + * + * \return 0 on success. + * #MBEDTLS_ERR_PK_TYPE_MISMATCH if \p pk does not contain + * a key of the type identified in \p attributes. + * Another error code on other failures. + */ +int mbedtls_pk_get_psa_attributes(const mbedtls_pk_context *pk, + psa_key_usage_t usage, + psa_key_attributes_t *attributes); + +/** + * \brief Import a key into the PSA key store. + * + * This function is equivalent to calling psa_import_key() + * with the key material from \p pk. + * + * The typical way to use this function is: + * -# Call mbedtls_pk_get_psa_attributes() to obtain + * attributes for the given key. + * -# If desired, modify the attributes, for example: + * - To create a persistent key, call + * psa_set_key_identifier() and optionally + * psa_set_key_lifetime(). + * - To import only the public part of a key pair: + * + * psa_set_key_type(&attributes, + * PSA_KEY_TYPE_PUBLIC_KEY_OF_KEY_PAIR( + * psa_get_key_type(&attributes))); + * - Restrict the key usage if desired. + * -# Call mbedtls_pk_import_into_psa(). + * + * \note This function does not support RSA-alt contexts + * (set up with mbedtls_pk_setup_rsa_alt()). + * + * \param[in] pk The PK context to use. It must have been set up. + * It can either contain a key pair or just a public key. + * \param[in] attributes + * The attributes to use for the new key. They must be + * compatible with \p pk. In particular, the key type + * must match the content of \p pk. + * If \p pk contains a key pair, the key type in + * attributes can be either the key pair type or the + * corresponding public key type (to import only the + * public part). + * \param[out] key_id + * On success, the identifier of the newly created key. + * On error, this is #MBEDTLS_SVC_KEY_ID_INIT. + * + * \return 0 on success. + * #MBEDTLS_ERR_PK_TYPE_MISMATCH if \p pk does not contain + * a key of the type identified in \p attributes. + * Another error code on other failures. + */ +int mbedtls_pk_import_into_psa(const mbedtls_pk_context *pk, + const psa_key_attributes_t *attributes, + mbedtls_svc_key_id_t *key_id); + +/** + * \brief Create a PK context starting from a key stored in PSA. + * This key: + * - must be exportable and + * - must be an RSA or EC key pair or public key (FFDH is not supported in PK). + * + * The resulting PK object will be a transparent type: + * - #MBEDTLS_PK_RSA for RSA keys or + * - #MBEDTLS_PK_ECKEY for EC keys. + * + * Once this functions returns the PK object will be completely + * independent from the original PSA key that it was generated + * from. + * Calling mbedtls_pk_sign(), mbedtls_pk_verify(), + * mbedtls_pk_encrypt(), mbedtls_pk_decrypt() on the resulting + * PK context will perform the corresponding algorithm for that + * PK context type. + * * For ECDSA, the choice of deterministic vs randomized will + * be based on the compile-time setting #MBEDTLS_ECDSA_DETERMINISTIC. + * * For an RSA key, the output PK context will allow both + * encrypt/decrypt and sign/verify regardless of the original + * key's policy. + * The original key's policy determines the output key's padding + * mode: PCKS1 v2.1 is set if the PSA key policy is OAEP or PSS, + * otherwise PKCS1 v1.5 is set. + * + * \param key_id The key identifier of the key stored in PSA. + * \param pk The PK context that will be filled. It must be initialized, + * but not set up. + * + * \return 0 on success. + * \return #MBEDTLS_ERR_PK_BAD_INPUT_DATA in case the provided input + * parameters are not correct. + */ +int mbedtls_pk_copy_from_psa(mbedtls_svc_key_id_t key_id, mbedtls_pk_context *pk); + +/** + * \brief Create a PK context for the public key of a PSA key. + * + * The key must be an RSA or ECC key. It can be either a + * public key or a key pair, and only the public key is copied. + * The resulting PK object will be a transparent type: + * - #MBEDTLS_PK_RSA for RSA keys or + * - #MBEDTLS_PK_ECKEY for EC keys. + * + * Once this functions returns the PK object will be completely + * independent from the original PSA key that it was generated + * from. + * Calling mbedtls_pk_verify() or + * mbedtls_pk_encrypt() on the resulting + * PK context will perform the corresponding algorithm for that + * PK context type. + * + * For an RSA key, the output PK context will allow both + * encrypt and verify regardless of the original key's policy. + * The original key's policy determines the output key's padding + * mode: PCKS1 v2.1 is set if the PSA key policy is OAEP or PSS, + * otherwise PKCS1 v1.5 is set. + * + * \param key_id The key identifier of the key stored in PSA. + * \param pk The PK context that will be filled. It must be initialized, + * but not set up. + * + * \return 0 on success. + * \return MBEDTLS_ERR_PK_BAD_INPUT_DATA in case the provided input + * parameters are not correct. + */ +int mbedtls_pk_copy_public_from_psa(mbedtls_svc_key_id_t key_id, mbedtls_pk_context *pk); +#endif /* MBEDTLS_PSA_CRYPTO_CLIENT */ + +/** + * \brief Verify signature (including padding if relevant). + * + * \param ctx The PK context to use. It must have been set up. + * \param md_alg Hash algorithm used. + * This can be #MBEDTLS_MD_NONE if the signature algorithm + * does not rely on a hash algorithm (non-deterministic + * ECDSA, RSA PKCS#1 v1.5). + * For PKCS#1 v1.5, if \p md_alg is #MBEDTLS_MD_NONE, then + * \p hash is the DigestInfo structure used by RFC 8017 + * §9.2 steps 3–6. If \p md_alg is a valid hash + * algorithm then \p hash is the digest itself, and this + * function calculates the DigestInfo encoding internally. + * \param hash Hash of the message to sign + * \param hash_len Hash length + * \param sig Signature to verify + * \param sig_len Signature length + * + * \note For keys of type #MBEDTLS_PK_RSA, the signature algorithm is + * either PKCS#1 v1.5 or PSS (accepting any salt length), + * depending on the padding mode in the underlying RSA context. + * For a pk object constructed by parsing, this is PKCS#1 v1.5 + * by default. Use mbedtls_pk_verify_ext() to explicitly select + * a different algorithm. + * + * \return 0 on success (signature is valid), + * #MBEDTLS_ERR_PK_SIG_LEN_MISMATCH if there is a valid + * signature in \p sig but its length is less than \p sig_len, + * or a specific error code. + */ +int mbedtls_pk_verify(mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg, + const unsigned char *hash, size_t hash_len, + const unsigned char *sig, size_t sig_len); + +/** + * \brief Restartable version of \c mbedtls_pk_verify() + * + * \note Performs the same job as \c mbedtls_pk_verify(), but can + * return early and restart according to the limit set with + * \c mbedtls_ecp_set_max_ops() to reduce blocking for ECC + * operations. For RSA, same as \c mbedtls_pk_verify(). + * + * \param ctx The PK context to use. It must have been set up. + * \param md_alg Hash algorithm used (see notes) + * \param hash Hash of the message to sign + * \param hash_len Hash length or 0 (see notes) + * \param sig Signature to verify + * \param sig_len Signature length + * \param rs_ctx Restart context (NULL to disable restart) + * + * \return See \c mbedtls_pk_verify(), or + * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of + * operations was reached: see \c mbedtls_ecp_set_max_ops(). + */ +int mbedtls_pk_verify_restartable(mbedtls_pk_context *ctx, + mbedtls_md_type_t md_alg, + const unsigned char *hash, size_t hash_len, + const unsigned char *sig, size_t sig_len, + mbedtls_pk_restart_ctx *rs_ctx); + +/** + * \brief Verify signature, with options. + * (Includes verification of the padding depending on type.) + * + * \param type Signature type (inc. possible padding type) to verify + * \param options Pointer to type-specific options, or NULL + * \param ctx The PK context to use. It must have been set up. + * \param md_alg Hash algorithm used (see notes) + * \param hash Hash of the message to sign + * \param hash_len Hash length or 0 (see notes) + * \param sig Signature to verify + * \param sig_len Signature length + * + * \return 0 on success (signature is valid), + * #MBEDTLS_ERR_PK_TYPE_MISMATCH if the PK context can't be + * used for this type of signatures, + * #MBEDTLS_ERR_PK_SIG_LEN_MISMATCH if there is a valid + * signature in \p sig but its length is less than \p sig_len, + * or a specific error code. + * + * \note If hash_len is 0, then the length associated with md_alg + * is used instead, or an error returned if it is invalid. + * + * \note md_alg may be MBEDTLS_MD_NONE, only if hash_len != 0 + * + * \note If type is MBEDTLS_PK_RSASSA_PSS, then options must point + * to a mbedtls_pk_rsassa_pss_options structure, + * otherwise it must be NULL. Note that if + * #MBEDTLS_USE_PSA_CRYPTO is defined, the salt length is not + * verified as PSA_ALG_RSA_PSS_ANY_SALT is used. + */ +int mbedtls_pk_verify_ext(mbedtls_pk_type_t type, const void *options, + mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg, + const unsigned char *hash, size_t hash_len, + const unsigned char *sig, size_t sig_len); + +/** + * \brief Make signature, including padding if relevant. + * + * \param ctx The PK context to use. It must have been set up + * with a private key. + * \param md_alg Hash algorithm used (see notes) + * \param hash Hash of the message to sign + * \param hash_len Hash length + * \param sig Place to write the signature. + * It must have enough room for the signature. + * #MBEDTLS_PK_SIGNATURE_MAX_SIZE is always enough. + * You may use a smaller buffer if it is large enough + * given the key type. + * \param sig_size The size of the \p sig buffer in bytes. + * \param sig_len On successful return, + * the number of bytes written to \p sig. + * \param f_rng RNG function, must not be \c NULL. + * \param p_rng RNG parameter + * + * \note For keys of type #MBEDTLS_PK_RSA, the signature algorithm is + * either PKCS#1 v1.5 or PSS (using the largest possible salt + * length up to the hash length), depending on the padding mode + * in the underlying RSA context. For a pk object constructed + * by parsing, this is PKCS#1 v1.5 by default. Use + * mbedtls_pk_verify_ext() to explicitly select a different + * algorithm. + * + * \return 0 on success, or a specific error code. + * + * \note For RSA, md_alg may be MBEDTLS_MD_NONE if hash_len != 0. + * For ECDSA, md_alg may never be MBEDTLS_MD_NONE. + */ +int mbedtls_pk_sign(mbedtls_pk_context *ctx, mbedtls_md_type_t md_alg, + const unsigned char *hash, size_t hash_len, + unsigned char *sig, size_t sig_size, size_t *sig_len, + int (*f_rng)(void *, unsigned char *, size_t), void *p_rng); + +/** + * \brief Make signature given a signature type. + * + * \param pk_type Signature type. + * \param ctx The PK context to use. It must have been set up + * with a private key. + * \param md_alg Hash algorithm used (see notes) + * \param hash Hash of the message to sign + * \param hash_len Hash length + * \param sig Place to write the signature. + * It must have enough room for the signature. + * #MBEDTLS_PK_SIGNATURE_MAX_SIZE is always enough. + * You may use a smaller buffer if it is large enough + * given the key type. + * \param sig_size The size of the \p sig buffer in bytes. + * \param sig_len On successful return, + * the number of bytes written to \p sig. + * \param f_rng RNG function, must not be \c NULL. + * \param p_rng RNG parameter + * + * \return 0 on success, or a specific error code. + * + * \note When \p pk_type is #MBEDTLS_PK_RSASSA_PSS, + * see #PSA_ALG_RSA_PSS for a description of PSS options used. + * + * \note For RSA, md_alg may be MBEDTLS_MD_NONE if hash_len != 0. + * For ECDSA, md_alg may never be MBEDTLS_MD_NONE. + * + */ +int mbedtls_pk_sign_ext(mbedtls_pk_type_t pk_type, + mbedtls_pk_context *ctx, + mbedtls_md_type_t md_alg, + const unsigned char *hash, size_t hash_len, + unsigned char *sig, size_t sig_size, size_t *sig_len, + int (*f_rng)(void *, unsigned char *, size_t), + void *p_rng); + +/** + * \brief Restartable version of \c mbedtls_pk_sign() + * + * \note Performs the same job as \c mbedtls_pk_sign(), but can + * return early and restart according to the limit set with + * \c mbedtls_ecp_set_max_ops() to reduce blocking for ECC + * operations. For RSA, same as \c mbedtls_pk_sign(). + * + * \param ctx The PK context to use. It must have been set up + * with a private key. + * \param md_alg Hash algorithm used (see notes for mbedtls_pk_sign()) + * \param hash Hash of the message to sign + * \param hash_len Hash length + * \param sig Place to write the signature. + * It must have enough room for the signature. + * #MBEDTLS_PK_SIGNATURE_MAX_SIZE is always enough. + * You may use a smaller buffer if it is large enough + * given the key type. + * \param sig_size The size of the \p sig buffer in bytes. + * \param sig_len On successful return, + * the number of bytes written to \p sig. + * \param f_rng RNG function, must not be \c NULL. + * \param p_rng RNG parameter + * \param rs_ctx Restart context (NULL to disable restart) + * + * \return See \c mbedtls_pk_sign(). + * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of + * operations was reached: see \c mbedtls_ecp_set_max_ops(). + */ +int mbedtls_pk_sign_restartable(mbedtls_pk_context *ctx, + mbedtls_md_type_t md_alg, + const unsigned char *hash, size_t hash_len, + unsigned char *sig, size_t sig_size, size_t *sig_len, + int (*f_rng)(void *, unsigned char *, size_t), void *p_rng, + mbedtls_pk_restart_ctx *rs_ctx); + +/** + * \brief Decrypt message (including padding if relevant). + * + * \param ctx The PK context to use. It must have been set up + * with a private key. + * \param input Input to decrypt + * \param ilen Input size + * \param output Decrypted output + * \param olen Decrypted message length + * \param osize Size of the output buffer + * \param f_rng RNG function, must not be \c NULL. + * \param p_rng RNG parameter + * + * \note For keys of type #MBEDTLS_PK_RSA, the signature algorithm is + * either PKCS#1 v1.5 or OAEP, depending on the padding mode in + * the underlying RSA context. For a pk object constructed by + * parsing, this is PKCS#1 v1.5 by default. + * + * \return 0 on success, or a specific error code. + */ +int mbedtls_pk_decrypt(mbedtls_pk_context *ctx, + const unsigned char *input, size_t ilen, + unsigned char *output, size_t *olen, size_t osize, + int (*f_rng)(void *, unsigned char *, size_t), void *p_rng); + +/** + * \brief Encrypt message (including padding if relevant). + * + * \param ctx The PK context to use. It must have been set up. + * \param input Message to encrypt + * \param ilen Message size + * \param output Encrypted output + * \param olen Encrypted output length + * \param osize Size of the output buffer + * \param f_rng RNG function, must not be \c NULL. + * \param p_rng RNG parameter + * + * \note For keys of type #MBEDTLS_PK_RSA, the signature algorithm is + * either PKCS#1 v1.5 or OAEP, depending on the padding mode in + * the underlying RSA context. For a pk object constructed by + * parsing, this is PKCS#1 v1.5 by default. + * + * \note \p f_rng is used for padding generation. + * + * \return 0 on success, or a specific error code. + */ +int mbedtls_pk_encrypt(mbedtls_pk_context *ctx, + const unsigned char *input, size_t ilen, + unsigned char *output, size_t *olen, size_t osize, + int (*f_rng)(void *, unsigned char *, size_t), void *p_rng); + +/** + * \brief Check if a public-private pair of keys matches. + * + * \param pub Context holding a public key. + * \param prv Context holding a private (and public) key. + * \param f_rng RNG function, must not be \c NULL. + * \param p_rng RNG parameter + * + * \return \c 0 on success (keys were checked and match each other). + * \return #MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE if the keys could not + * be checked - in that case they may or may not match. + * \return #MBEDTLS_ERR_PK_BAD_INPUT_DATA if a context is invalid. + * \return Another non-zero value if the keys do not match. + */ +int mbedtls_pk_check_pair(const mbedtls_pk_context *pub, + const mbedtls_pk_context *prv, + int (*f_rng)(void *, unsigned char *, size_t), + void *p_rng); + +/** + * \brief Export debug information + * + * \param ctx The PK context to use. It must have been initialized. + * \param items Place to write debug items + * + * \return 0 on success or MBEDTLS_ERR_PK_BAD_INPUT_DATA + */ +int mbedtls_pk_debug(const mbedtls_pk_context *ctx, mbedtls_pk_debug_item *items); + +/** + * \brief Access the type name + * + * \param ctx The PK context to use. It must have been initialized. + * + * \return Type name on success, or "invalid PK" + */ +const char *mbedtls_pk_get_name(const mbedtls_pk_context *ctx); + +/** + * \brief Get the key type + * + * \param ctx The PK context to use. It must have been initialized. + * + * \return Type on success. + * \return #MBEDTLS_PK_NONE for a context that has not been set up. + */ +mbedtls_pk_type_t mbedtls_pk_get_type(const mbedtls_pk_context *ctx); + +#if defined(MBEDTLS_RSA_C) +/** + * Quick access to an RSA context inside a PK context. + * + * \warning This function can only be used when the type of the context, as + * returned by mbedtls_pk_get_type(), is #MBEDTLS_PK_RSA. + * Ensuring that is the caller's responsibility. + * Alternatively, you can check whether this function returns NULL. + * + * \return The internal RSA context held by the PK context, or NULL. + */ +static inline mbedtls_rsa_context *mbedtls_pk_rsa(const mbedtls_pk_context pk) +{ + switch (mbedtls_pk_get_type(&pk)) { + case MBEDTLS_PK_RSA: + return (mbedtls_rsa_context *) (pk).MBEDTLS_PRIVATE(pk_ctx); + default: + return NULL; + } +} +#endif /* MBEDTLS_RSA_C */ + +#if defined(MBEDTLS_ECP_C) +/** + * Quick access to an EC context inside a PK context. + * + * \warning This function can only be used when the type of the context, as + * returned by mbedtls_pk_get_type(), is #MBEDTLS_PK_ECKEY, + * #MBEDTLS_PK_ECKEY_DH, or #MBEDTLS_PK_ECDSA. + * Ensuring that is the caller's responsibility. + * Alternatively, you can check whether this function returns NULL. + * + * \return The internal EC context held by the PK context, or NULL. + */ +static inline mbedtls_ecp_keypair *mbedtls_pk_ec(const mbedtls_pk_context pk) +{ + switch (mbedtls_pk_get_type(&pk)) { + case MBEDTLS_PK_ECKEY: + case MBEDTLS_PK_ECKEY_DH: + case MBEDTLS_PK_ECDSA: + return (mbedtls_ecp_keypair *) (pk).MBEDTLS_PRIVATE(pk_ctx); + default: + return NULL; + } +} +#endif /* MBEDTLS_ECP_C */ + +#if defined(MBEDTLS_PK_PARSE_C) +/** \ingroup pk_module */ +/** + * \brief Parse a private key in PEM or DER format + * + * \note If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto + * subsystem must have been initialized by calling + * psa_crypto_init() before calling this function. + * + * \param ctx The PK context to fill. It must have been initialized + * but not set up. + * \param key Input buffer to parse. + * The buffer must contain the input exactly, with no + * extra trailing material. For PEM, the buffer must + * contain a null-terminated string. + * \param keylen Size of \b key in bytes. + * For PEM data, this includes the terminating null byte, + * so \p keylen must be equal to `strlen(key) + 1`. + * \param pwd Optional password for decryption. + * Pass \c NULL if expecting a non-encrypted key. + * Pass a string of \p pwdlen bytes if expecting an encrypted + * key; a non-encrypted key will also be accepted. + * The empty password is not supported. + * \param pwdlen Size of the password in bytes. + * Ignored if \p pwd is \c NULL. + * \param f_rng RNG function, must not be \c NULL. Used for blinding. + * \param p_rng RNG parameter + * + * \note On entry, ctx must be empty, either freshly initialised + * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a + * specific key type, check the result with mbedtls_pk_can_do(). + * + * \note The key is also checked for correctness. + * + * \return 0 if successful, or a specific PK or PEM error code + */ +int mbedtls_pk_parse_key(mbedtls_pk_context *ctx, + const unsigned char *key, size_t keylen, + const unsigned char *pwd, size_t pwdlen, + int (*f_rng)(void *, unsigned char *, size_t), void *p_rng); + +/** \ingroup pk_module */ +/** + * \brief Parse a public key in PEM or DER format + * + * \note If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto + * subsystem must have been initialized by calling + * psa_crypto_init() before calling this function. + * + * \param ctx The PK context to fill. It must have been initialized + * but not set up. + * \param key Input buffer to parse. + * The buffer must contain the input exactly, with no + * extra trailing material. For PEM, the buffer must + * contain a null-terminated string. + * \param keylen Size of \b key in bytes. + * For PEM data, this includes the terminating null byte, + * so \p keylen must be equal to `strlen(key) + 1`. + * + * \note On entry, ctx must be empty, either freshly initialised + * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a + * specific key type, check the result with mbedtls_pk_can_do(). + * + * \note For compressed points, see #MBEDTLS_ECP_PF_COMPRESSED for + * limitations. + * + * \note The key is also checked for correctness. + * + * \return 0 if successful, or a specific PK or PEM error code + */ +int mbedtls_pk_parse_public_key(mbedtls_pk_context *ctx, + const unsigned char *key, size_t keylen); + +#if defined(MBEDTLS_FS_IO) +/** \ingroup pk_module */ +/** + * \brief Load and parse a private key + * + * \note If #MBEDTLS_USE_PSA_CRYPTO is enabled, the PSA crypto + * subsystem must have been initialized by calling + * psa_crypto_init() before calling this function. + * + * \param ctx The PK context to fill. It must have been initialized + * but not set up. + * \param path filename to read the private key from + * \param password Optional password to decrypt the file. + * Pass \c NULL if expecting a non-encrypted key. + * Pass a null-terminated string if expecting an encrypted + * key; a non-encrypted key will also be accepted. + * The empty password is not supported. + * \param f_rng RNG function, must not be \c NULL. Used for blinding. + * \param p_rng RNG parameter + * + * \note On entry, ctx must be empty, either freshly initialised + * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a + * specific key type, check the result with mbedtls_pk_can_do(). + * + * \note The key is also checked for correctness. + * + * \return 0 if successful, or a specific PK or PEM error code + */ +int mbedtls_pk_parse_keyfile(mbedtls_pk_context *ctx, + const char *path, const char *password, + int (*f_rng)(void *, unsigned char *, size_t), void *p_rng); + +/** \ingroup pk_module */ +/** + * \brief Load and parse a public key + * + * \param ctx The PK context to fill. It must have been initialized + * but not set up. + * \param path filename to read the public key from + * + * \note On entry, ctx must be empty, either freshly initialised + * with mbedtls_pk_init() or reset with mbedtls_pk_free(). If + * you need a specific key type, check the result with + * mbedtls_pk_can_do(). + * + * \note The key is also checked for correctness. + * + * \return 0 if successful, or a specific PK or PEM error code + */ +int mbedtls_pk_parse_public_keyfile(mbedtls_pk_context *ctx, const char *path); +#endif /* MBEDTLS_FS_IO */ +#endif /* MBEDTLS_PK_PARSE_C */ + +#if defined(MBEDTLS_PK_WRITE_C) +/** + * \brief Write a private key to a PKCS#1 or SEC1 DER structure + * Note: data is written at the end of the buffer! Use the + * return value to determine where you should start + * using the buffer + * + * \param ctx PK context which must contain a valid private key. + * \param buf buffer to write to + * \param size size of the buffer + * + * \return length of data written if successful, or a specific + * error code + */ +int mbedtls_pk_write_key_der(const mbedtls_pk_context *ctx, unsigned char *buf, size_t size); + +/** + * \brief Write a public key to a SubjectPublicKeyInfo DER structure + * Note: data is written at the end of the buffer! Use the + * return value to determine where you should start + * using the buffer + * + * \param ctx PK context which must contain a valid public or private key. + * \param buf buffer to write to + * \param size size of the buffer + * + * \return length of data written if successful, or a specific + * error code + */ +int mbedtls_pk_write_pubkey_der(const mbedtls_pk_context *ctx, unsigned char *buf, size_t size); + +#if defined(MBEDTLS_PEM_WRITE_C) +/** + * \brief Write a public key to a PEM string + * + * \param ctx PK context which must contain a valid public or private key. + * \param buf Buffer to write to. The output includes a + * terminating null byte. + * \param size Size of the buffer in bytes. + * + * \return 0 if successful, or a specific error code + */ +int mbedtls_pk_write_pubkey_pem(const mbedtls_pk_context *ctx, unsigned char *buf, size_t size); + +/** + * \brief Write a private key to a PKCS#1 or SEC1 PEM string + * + * \param ctx PK context which must contain a valid private key. + * \param buf Buffer to write to. The output includes a + * terminating null byte. + * \param size Size of the buffer in bytes. + * + * \return 0 if successful, or a specific error code + */ +int mbedtls_pk_write_key_pem(const mbedtls_pk_context *ctx, unsigned char *buf, size_t size); +#endif /* MBEDTLS_PEM_WRITE_C */ +#endif /* MBEDTLS_PK_WRITE_C */ + +/* + * WARNING: Low-level functions. You probably do not want to use these unless + * you are certain you do ;) + */ + +#if defined(MBEDTLS_PK_PARSE_C) +/** + * \brief Parse a SubjectPublicKeyInfo DER structure + * + * \param p the position in the ASN.1 data + * \param end end of the buffer + * \param pk The PK context to fill. It must have been initialized + * but not set up. + * + * \return 0 if successful, or a specific PK error code + */ +int mbedtls_pk_parse_subpubkey(unsigned char **p, const unsigned char *end, + mbedtls_pk_context *pk); +#endif /* MBEDTLS_PK_PARSE_C */ + +#if defined(MBEDTLS_PK_WRITE_C) +/** + * \brief Write a subjectPublicKey to ASN.1 data + * Note: function works backwards in data buffer + * + * \param p reference to current position pointer + * \param start start of the buffer (for bounds-checking) + * \param key PK context which must contain a valid public or private key. + * + * \return the length written or a negative error code + */ +int mbedtls_pk_write_pubkey(unsigned char **p, unsigned char *start, + const mbedtls_pk_context *key); +#endif /* MBEDTLS_PK_WRITE_C */ + +#ifdef __cplusplus +} +#endif + +#endif /* MBEDTLS_PK_H */ |