Document parameter preconditions in ECP module
diff --git a/include/mbedtls/ecp.h b/include/mbedtls/ecp.h
index 1c37298..9f4c3e5 100644
--- a/include/mbedtls/ecp.h
+++ b/include/mbedtls/ecp.h
@@ -497,24 +497,37 @@
/**
* \brief This function frees the components of an ECP group.
- * \param grp The group to free.
+ *
+ * \param grp The group to free. This may be \c NULL, in which
+ * case this function is a no-op. If it is not \c NULL,
+ * it must point to an initialized ECP group.
*/
void mbedtls_ecp_group_free( mbedtls_ecp_group *grp );
/**
* \brief This function frees the components of a key pair.
- * \param key The key pair to free.
+ *
+ * \param key The key pair to free. This may be \c NULL, in which
+ * case this function is a no-op. If it is not \c NULL,
+ * it must point to an initialized ECP key pair.
*/
void mbedtls_ecp_keypair_free( mbedtls_ecp_keypair *key );
#if defined(MBEDTLS_ECP_RESTARTABLE)
/**
- * \brief Initialize a restart context
+ * \brief Initialize a restart context.
+ *
+ * \param ctx The restart context to initialize. This must
+ * not be \c NULL.
*/
void mbedtls_ecp_restart_init( mbedtls_ecp_restart_ctx *ctx );
/**
- * \brief Free the components of a restart context
+ * \brief Free the components of a restart context.
+ *
+ * \param ctx The restart context to free. This may be \c NULL, in which
+ * case this function is a no-op. If it is not \c NULL,
+ * it must point to an initialized restart context.
*/
void mbedtls_ecp_restart_free( mbedtls_ecp_restart_ctx *ctx );
#endif /* MBEDTLS_ECP_RESTARTABLE */
@@ -523,11 +536,12 @@
* \brief This function copies the contents of point \p Q into
* point \p P.
*
- * \param P The destination point.
- * \param Q The source point.
+ * \param P The destination point. This must be initialized.
+ * \param Q The source point. This must be initialized.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
+ * \return Another negative error code for other kinds of failure.
*/
int mbedtls_ecp_copy( mbedtls_ecp_point *P, const mbedtls_ecp_point *Q );
@@ -535,31 +549,35 @@
* \brief This function copies the contents of group \p src into
* group \p dst.
*
- * \param dst The destination group.
- * \param src The source group.
+ * \param dst The destination group. This must be initialized.
+ * \param src The source group. This must be initialized.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
+ * \return Another negative error code on other kinds of failure.
*/
-int mbedtls_ecp_group_copy( mbedtls_ecp_group *dst, const mbedtls_ecp_group *src );
+int mbedtls_ecp_group_copy( mbedtls_ecp_group *dst,
+ const mbedtls_ecp_group *src );
/**
- * \brief This function sets a point to zero.
+ * \brief This function sets a point to the point at infinity.
*
- * \param pt The point to set.
+ * \param pt The point to set. This must be initialized.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
+ * \return Another negative error code on other kinds of failure.
*/
int mbedtls_ecp_set_zero( mbedtls_ecp_point *pt );
/**
- * \brief This function checks if a point is zero.
+ * \brief This function checks if a point is the point at infinity.
*
- * \param pt The point to test.
+ * \param pt The point to test. This must be initialized.
*
* \return \c 1 if the point is zero.
* \return \c 0 if the point is non-zero.
+ * \return A negative error code on failure.
*/
int mbedtls_ecp_is_zero( mbedtls_ecp_point *pt );
@@ -569,8 +587,8 @@
* \note This assumes that the points are normalized. Otherwise,
* they may compare as "not equal" even if they are.
*
- * \param P The first point to compare.
- * \param Q The second point to compare.
+ * \param P The first point to compare. This must be initialized.
+ * \param Q The second point to compare. This must be initialized.
*
* \return \c 0 if the points are equal.
* \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the points are not equal.
@@ -582,7 +600,7 @@
* \brief This function imports a non-zero point from two ASCII
* strings.
*
- * \param P The destination point.
+ * \param P The destination point. This must be initialized.
* \param radix The numeric base of the input.
* \param x The first affine coordinate, as a null-terminated string.
* \param y The second affine coordinate, as a null-terminated string.
@@ -597,15 +615,21 @@
* \brief This function exports a point into unsigned binary data.
*
* \param grp The group to which the point should belong.
- * \param P The point to export.
- * \param format The point format. Should be an \c MBEDTLS_ECP_PF_XXX macro.
- * \param olen The length of the output.
- * \param buf The output buffer.
- * \param buflen The length of the output buffer.
+ * This must be initialized and have group parameters
+ * set, for example through mbedtls_ecp_group_load().
+ * \param P The point to export. This must be initialized.
+ * \param format The point format. This must be either
+ * #MBEDTLS_ECP_PF_COMPRESSED or #MBEDTLS_ECP_PF_UNCOMPRESSED.
+ * \param olen The address at which to store the length of
+ * the output in Bytes.
+ * \param buf The output buffer. This must be a writable buffer
+ * of length \p buflen Bytes.
+ * \param buflen The length of the output buffer \p buf in Bytes.
*
* \return \c 0 on success.
- * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA
- * or #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL on failure.
+ * \return #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL if the output buffer
+ * is too small to hold the point.
+ * \return Another negative error code on other kinds of failure.
*/
int mbedtls_ecp_point_write_binary( const mbedtls_ecp_group *grp, const mbedtls_ecp_point *P,
int format, size_t *olen,
@@ -619,19 +643,23 @@
* for that.
*
* \param grp The group to which the point should belong.
- * \param P The point to import.
- * \param buf The input buffer.
- * \param ilen The length of the input.
+ * This must be initialized and have group parameters
+ * set, for example through mbedtls_ecp_group_load().
+ * \param P The destination context to import the point to.
+ * This must be initialized.
+ * \param buf The input buffer. This must be a readable buffer
+ * of length \p ilen Bytes.
+ * \param ilen The length of the input buffer \p buf in Bytes.
*
* \return \c 0 on success.
- * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid.
+ * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the input is invalid.
* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
* \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the point format
* is not implemented.
- *
*/
-int mbedtls_ecp_point_read_binary( const mbedtls_ecp_group *grp, mbedtls_ecp_point *P,
- const unsigned char *buf, size_t ilen );
+int mbedtls_ecp_point_read_binary( const mbedtls_ecp_group *grp,
+ mbedtls_ecp_point *P,
+ const unsigned char *buf, size_t ilen );
/**
* \brief This function imports a point from a TLS ECPoint record.
@@ -639,7 +667,9 @@
* \note On function return, \p *buf is updated to point immediately
* after the ECPoint record.
*
- * \param grp The ECP group used.
+ * \param grp The ECP group to use.
+ * This must be initialized and have group parameters
+ * set, for example through mbedtls_ecp_group_load().
* \param pt The destination point.
* \param buf The address of the pointer to the start of the input buffer.
* \param len The length of the buffer.
@@ -649,99 +679,122 @@
* failure.
* \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid.
*/
-int mbedtls_ecp_tls_read_point( const mbedtls_ecp_group *grp, mbedtls_ecp_point *pt,
- const unsigned char **buf, size_t len );
+int mbedtls_ecp_tls_read_point( const mbedtls_ecp_group *grp,
+ mbedtls_ecp_point *pt,
+ const unsigned char **buf, size_t len );
/**
- * \brief This function exports a point as a TLS ECPoint record.
+ * \brief This function exports a point as a TLS ECPoint record
+ * defined in RFC 4492, Section 5.4.
*
- * \param grp The ECP group used.
- * \param pt The point format to export to. The point format is an
- * \c MBEDTLS_ECP_PF_XXX constant.
- * \param format The export format.
- * \param olen The length of the data written.
- * \param buf The buffer to write to.
- * \param blen The length of the buffer.
+ * \param grp The ECP group to use.
+ * This must be initialized and have group parameters
+ * set, for example through mbedtls_ecp_group_load().
+ * \param pt The point to be exported. This must be initialized.
+ * \param format The point format to use. This must be either
+ * #MBEDTLS_ECP_PF_COMPRESSED or #MBEDTLS_ECP_PF_UNCOMPRESSED.
+ * \param olen The address at which to store the length in Bytes
+ * of the data written.
+ * \param buf The target buffer. This must be a writable buffer of
+ * length \p blen Bytes.
+ * \param blen The length of the target buffer \p buf in Bytes.
*
* \return \c 0 on success.
- * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA or
- * #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL on failure.
+ * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the input is invalid.
+ * \return #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL if the target buffer
+ * is too small to hold the exported point.
+ * \return Another negative error code on other kinds of failure.
*/
-int mbedtls_ecp_tls_write_point( const mbedtls_ecp_group *grp, const mbedtls_ecp_point *pt,
- int format, size_t *olen,
- unsigned char *buf, size_t blen );
+int mbedtls_ecp_tls_write_point( const mbedtls_ecp_group *grp,
+ const mbedtls_ecp_point *pt,
+ int format, size_t *olen,
+ unsigned char *buf, size_t blen );
/**
- * \brief This function sets a group using standardized domain parameters.
+ * \brief This function sets up an ECP group context
+ * from a standardized set of domain parameters.
*
* \note The index should be a value of the NamedCurve enum,
* as defined in <em>RFC-4492: Elliptic Curve Cryptography
* (ECC) Cipher Suites for Transport Layer Security (TLS)</em>,
* usually in the form of an \c MBEDTLS_ECP_DP_XXX macro.
*
- * \param grp The destination group.
+ * \param grp The group context to setup. This must be initialized.
* \param id The identifier of the domain parameter set to load.
*
- * \return \c 0 on success,
- * \return An \c MBEDTLS_ERR_MPI_XXX error code on initialization failure.
- * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE for unkownn groups.
-
+ * \return \c 0 on success.
+ * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if \p id doesn't
+ * correspond to a known group.
+ * \return Another negative error code on other kinds of failure.
*/
int mbedtls_ecp_group_load( mbedtls_ecp_group *grp, mbedtls_ecp_group_id id );
/**
- * \brief This function sets a group from a TLS ECParameters record.
+ * \brief This function sets up an ECP group context from a TLS
+ * ECParameters record as defined in RFC 4492, Section 5.4.
*
- * \note \p buf is updated to point right after the ECParameters
- * record on exit.
+ * \note The read pointer \p buf is updated to point right after
+ * the ECParameters record on exit.
*
- * \param grp The destination group.
+ * \param grp The group context to setup. This must be initialized.
* \param buf The address of the pointer to the start of the input buffer.
- * \param len The length of the buffer.
+ * \param len The length of the input buffer \c *buf in Bytes.
*
* \return \c 0 on success.
- * \return An \c MBEDTLS_ERR_MPI_XXX error code on initialization
- * failure.
* \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid.
* \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the group is not
- * recognised.
+ * recognized.
+ * \return Another negative error code on other kinds of failure.
*/
-int mbedtls_ecp_tls_read_group( mbedtls_ecp_group *grp, const unsigned char **buf, size_t len );
+int mbedtls_ecp_tls_read_group( mbedtls_ecp_group *grp,
+ const unsigned char **buf, size_t len );
/**
- * \brief This function reads a group from a TLS ECParameters record.
+ * \brief This function extracts an elliptic curve group ID from a
+ * TLS ECParameters record as defined in RFC 4492, Section 5.4.
*
- * \note \p buf is updated to point right after the ECParameters
- * record on exit.
+ * \note The read pointer \p buf is updated to point right after
+ * the ECParameters record on exit.
*
- * \param grp Output parameter to hold the group id.
+ * \param grp The address at which to store the group id.
+ * This must not be \c NULL.
* \param buf The address of the pointer to the start of the input buffer.
- * \param len The length of the buffer.
+ * \param len The length of the input buffer \c *buf in Bytes.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid.
* \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the group is not
- * recognised.
+ * recognized.
+ * \return Another negative error code on other kinds of failure.
*/
int mbedtls_ecp_tls_read_group_id( mbedtls_ecp_group_id *grp,
- const unsigned char **buf, size_t len );
+ const unsigned char **buf,
+ size_t len );
/**
- * \brief This function writes the TLS ECParameters record for a group.
+ * \brief This function exports an elliptic curve as a TLS
+ * ECParameters record as defined in RFC 4492, Section 5.4.
*
- * \param grp The ECP group used.
- * \param olen The number of Bytes written.
- * \param buf The buffer to write to.
- * \param blen The length of the buffer.
+ * \param grp The ECP group to be exported.
+ * This must be initialized and have group parameters
+ * set, for example through mbedtls_ecp_group_load().
+ * \param olen The address at which to store the number of Bytes written.
+ * This must not be \c NULL.
+ * \param buf The buffer to write to. This must be a writable buffer
+ * of length \p blen Bytes.
+ * \param blen The length of the output buffer \p buf in Bytes.
*
* \return \c 0 on success.
- * \return #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL on failure.
+ * \return #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL if the output
+ * buffer is too small to hold the exported group.
+ * \return Another negative error code on other kinds of failure.
*/
-int mbedtls_ecp_tls_write_group( const mbedtls_ecp_group *grp, size_t *olen,
- unsigned char *buf, size_t blen );
+int mbedtls_ecp_tls_write_group( const mbedtls_ecp_group *grp,
+ size_t *olen,
+ unsigned char *buf, size_t blen );
/**
- * \brief This function performs multiplication of a point by
- * an integer: \p R = \p m * \p P.
+ * \brief This function performs a scalaar multiplication of a point
+ * by an integer: \p R = \p m * \p P.
*
* It is not thread-safe to use same group in multiple threads.
*
@@ -755,17 +808,22 @@
* targeting these results. We recommend always providing
* a non-NULL \p f_rng. The overhead is negligible.
*
- * \param grp The ECP group.
- * \param R The destination point.
- * \param m The integer by which to multiply.
- * \param P The point to multiply.
- * \param f_rng The RNG function.
- * \param p_rng The RNG context.
+ * \param grp The ECP group to use.
+ * This must be initialized and have group parameters
+ * set, for example through mbedtls_ecp_group_load().
+ * \param R The point in which to store the result of the calculation.
+ * This must be initialized.
+ * \param m The integer by which to multiply. This must be initialized.
+ * \param P The point to multiply. This must be initialized.
+ * \param f_rng The RNG function. This may be \c NULL if randomization
+ * of intermediate results isn't desired (discouraged).
+ * \param p_rng The RNG context to be passed to \p p_rng.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_ECP_INVALID_KEY if \p m is not a valid private
* key, or \p P is not a valid public key.
* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
+ * \return Another negative error code on other kinds of failure.
*/
int mbedtls_ecp_mul( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
const mbedtls_mpi *m, const mbedtls_ecp_point *P,
@@ -781,12 +839,16 @@
* it can return early and restart according to the limit set
* with \c mbedtls_ecp_set_max_ops() to reduce blocking.
*
- * \param grp The ECP group.
- * \param R The destination point.
- * \param m The integer by which to multiply.
- * \param P The point to multiply.
- * \param f_rng The RNG function.
- * \param p_rng The RNG context.
+ * \param grp The ECP group to use.
+ * This must be initialized and have group parameters
+ * set, for example through mbedtls_ecp_group_load().
+ * \param R The point in which to store the result of the calculation.
+ * This must be initialized.
+ * \param m The integer by which to multiply. This must be initialized.
+ * \param P The point to multiply. This must be initialized.
+ * \param f_rng The RNG function. This may be \c NULL if randomization
+ * of intermediate results isn't desired (discouraged).
+ * \param p_rng The RNG context to be passed to \p p_rng.
* \param rs_ctx The restart context (NULL disables restart).
*
* \return \c 0 on success.
@@ -795,6 +857,7 @@
* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
* \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
* operations was reached: see \c mbedtls_ecp_set_max_ops().
+ * \return Another negative error code on other kinds of failure.
*/
int mbedtls_ecp_mul_restartable( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
const mbedtls_mpi *m, const mbedtls_ecp_point *P,
@@ -810,18 +873,25 @@
* \note In contrast to mbedtls_ecp_mul(), this function does not
* guarantee a constant execution flow and timing.
*
- * \param grp The ECP group.
- * \param R The destination point.
+ * \param grp The ECP group to use.
+ * This must be initialized and have group parameters
+ * set, for example through mbedtls_ecp_group_load().
+ * \param R The point in which to store the result of the calculation.
+ * This must be initialized.
* \param m The integer by which to multiply \p P.
- * \param P The point to multiply by \p m.
+ * This must be initialized.
+ * \param P The point to multiply by \p m. This must be initialized.
* \param n The integer by which to multiply \p Q.
+ * This must be initialized.
* \param Q The point to be multiplied by \p n.
+ * This must be initialized.
*
* \return \c 0 on success.
* \return #MBEDTLS_ERR_ECP_INVALID_KEY if \p m or \p n are not
* valid private keys, or \p P or \p Q are not valid public
* keys.
* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
+ * \return Another negative error code on other kinds of failure.
*/
int mbedtls_ecp_muladd( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
const mbedtls_mpi *m, const mbedtls_ecp_point *P,
@@ -838,12 +908,18 @@
* but it can return early and restart according to the limit
* set with \c mbedtls_ecp_set_max_ops() to reduce blocking.
*
- * \param grp The ECP group.
- * \param R The destination point.
+ * \param grp The ECP group to use.
+ * This must be initialized and have group parameters
+ * set, for example through mbedtls_ecp_group_load().
+ * \param R The point in which to store the result of the calculation.
+ * This must be initialized.
* \param m The integer by which to multiply \p P.
- * \param P The point to multiply by \p m.
+ * This must be initialized.
+ * \param P The point to multiply by \p m. This must be initialized.
* \param n The integer by which to multiply \p Q.
+ * This must be initialized.
* \param Q The point to be multiplied by \p n.
+ * This must be initialized.
* \param rs_ctx The restart context (NULL disables restart).
*
* \return \c 0 on success.
@@ -853,6 +929,7 @@
* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
* \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
* operations was reached: see \c mbedtls_ecp_set_max_ops().
+ * \return Another negative error code on other kinds of failure.
*/
int mbedtls_ecp_muladd_restartable(
mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
@@ -877,38 +954,51 @@
* structures, such as ::mbedtls_ecdh_context or
* ::mbedtls_ecdsa_context.
*
- * \param grp The curve the point should lie on.
- * \param pt The point to check.
+ * \param grp The ECP group the point should belong to.
+ * This must be initialized and have group parameters
+ * set, for example through mbedtls_ecp_group_load().
+ * \param pt The point to check. This must be initialized.
*
* \return \c 0 if the point is a valid public key.
- * \return #MBEDTLS_ERR_ECP_INVALID_KEY on failure.
+ * \return #MBEDTLS_ERR_ECP_INVALID_KEY if the point is not
+ * a valid public key for the given curve.
+ * \return Another negative error code on other kinds of failure.
*/
-int mbedtls_ecp_check_pubkey( const mbedtls_ecp_group *grp, const mbedtls_ecp_point *pt );
+int mbedtls_ecp_check_pubkey( const mbedtls_ecp_group *grp,
+ const mbedtls_ecp_point *pt );
/**
- * \brief This function checks that an \p mbedtls_mpi is a valid private
- * key for this curve.
+ * \brief This function checks that an \p mbedtls_mpi is a
+ * valid private key for this curve.
*
* \note This function uses bare components rather than an
* ::mbedtls_ecp_keypair structure to ease use with other
* structures, such as ::mbedtls_ecdh_context or
* ::mbedtls_ecdsa_context.
*
- * \param grp The group used.
- * \param d The integer to check.
+ * \param grp The ECP group the private key should belong to.
+ * This must be initialized and have group parameters
+ * set, for example through mbedtls_ecp_group_load().
+ * \param d The integer to check. This must be initialized.
*
* \return \c 0 if the point is a valid private key.
- * \return #MBEDTLS_ERR_ECP_INVALID_KEY on failure.
+ * \return #MBEDTLS_ERR_ECP_INVALID_KEY if the point is not a valid
+ * private key for the given curve.
+ * \return Another negative error code on other kinds of failure.
*/
-int mbedtls_ecp_check_privkey( const mbedtls_ecp_group *grp, const mbedtls_mpi *d );
+int mbedtls_ecp_check_privkey( const mbedtls_ecp_group *grp,
+ const mbedtls_mpi *d );
/**
* \brief This function generates a private key.
*
- * \param grp The ECP group.
- * \param d The destination MPI (secret part).
- * \param f_rng The RNG function.
- * \param p_rng The RNG parameter.
+ * \param grp The ECP group to generate a private key for.
+ * This must be initialized and have group parameters
+ * set, for example through mbedtls_ecp_group_load().
+ * \param d The destination MPI (secret part). This must be initialized.
+ * \param f_rng The RNG function. This must not be \c NULL.
+ * \param p_rng The RNG parameter to be passed to \p f_rng. This may be
+ * \c NULL if \p f_rng doesn't need a context argument.
*
* \return \c 0 on success.
* \return An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code
@@ -928,22 +1018,29 @@
* structures, such as ::mbedtls_ecdh_context or
* ::mbedtls_ecdsa_context.
*
- * \param grp The ECP group.
- * \param G The chosen base point.
+ * \param grp The ECP group to generate a key pair for.
+ * This must be initialized and have group parameters
+ * set, for example through mbedtls_ecp_group_load().
+ * \param G The base point to use. This must be initialized
+ * and belong to \p grp. It replaces the default base
+ * point \c grp->G used by mbedtls_ecp_gen_keypair().
* \param d The destination MPI (secret part).
+ * This must be initialized.
* \param Q The destination point (public part).
- * \param f_rng The RNG function.
- * \param p_rng The RNG context.
+ * This must be initialized.
+ * \param f_rng The RNG function. This must not be \c NULL.
+ * \param p_rng The RNG context to be passed to \p f_rng. This may
+ * be \c NULL if \p f_rng doesn't need a context argument.
*
* \return \c 0 on success.
* \return An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code
* on failure.
*/
int mbedtls_ecp_gen_keypair_base( mbedtls_ecp_group *grp,
- const mbedtls_ecp_point *G,
- mbedtls_mpi *d, mbedtls_ecp_point *Q,
- int (*f_rng)(void *, unsigned char *, size_t),
- void *p_rng );
+ const mbedtls_ecp_point *G,
+ mbedtls_mpi *d, mbedtls_ecp_point *Q,
+ int (*f_rng)(void *, unsigned char *, size_t),
+ void *p_rng );
/**
* \brief This function generates an ECP keypair.
@@ -953,34 +1050,42 @@
* structures, such as ::mbedtls_ecdh_context or
* ::mbedtls_ecdsa_context.
*
- * \param grp The ECP group.
+ * \param grp The ECP group to generate a key pair for.
+ * This must be initialized and have group parameters
+ * set, for example through mbedtls_ecp_group_load().
* \param d The destination MPI (secret part).
+ * This must be initialized.
* \param Q The destination point (public part).
- * \param f_rng The RNG function.
- * \param p_rng The RNG context.
+ * This must be initialized.
+ * \param f_rng The RNG function. This must not be \c NULL.
+ * \param p_rng The RNG context to be passed to \p f_rng. This may
+ * be \c NULL if \p f_rng doesn't need a context argument.
*
* \return \c 0 on success.
* \return An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code
* on failure.
*/
-int mbedtls_ecp_gen_keypair( mbedtls_ecp_group *grp, mbedtls_mpi *d, mbedtls_ecp_point *Q,
- int (*f_rng)(void *, unsigned char *, size_t),
- void *p_rng );
+int mbedtls_ecp_gen_keypair( mbedtls_ecp_group *grp, mbedtls_mpi *d,
+ mbedtls_ecp_point *Q,
+ int (*f_rng)(void *, unsigned char *, size_t),
+ void *p_rng );
/**
* \brief This function generates an ECP key.
*
* \param grp_id The ECP group identifier.
- * \param key The destination key.
- * \param f_rng The RNG function.
- * \param p_rng The RNG context.
+ * \param key The destination key. This must be initialized.
+ * \param f_rng The RNG function to use. This must not be \c NULL.
+ * \param p_rng The RNG context to be passed to \p f_rng. This may
+ * be \c NULL if \p f_rng doesn't need a context argument.
*
* \return \c 0 on success.
* \return An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code
* on failure.
*/
int mbedtls_ecp_gen_key( mbedtls_ecp_group_id grp_id, mbedtls_ecp_keypair *key,
- int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
+ int (*f_rng)(void *, unsigned char *, size_t),
+ void *p_rng );
/**
* \brief This function checks that the keypair objects
@@ -988,16 +1093,19 @@
* same public point, and that the private key in
* \p prv is consistent with the public key.
*
- * \param pub The keypair structure holding the public key.
- * If it contains a private key, that part is ignored.
+ * \param pub The keypair structure holding the public key. This
+ * must be initialized. If it contains a private key, that
+ * part is ignored.
* \param prv The keypair structure holding the full keypair.
+ * This must be initialized.
*
* \return \c 0 on success, meaning that the keys are valid and match.
* \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the keys are invalid or do not match.
* \return An \c MBEDTLS_ERR_ECP_XXX or an \c MBEDTLS_ERR_MPI_XXX
* error code on calculation failure.
*/
-int mbedtls_ecp_check_pub_priv( const mbedtls_ecp_keypair *pub, const mbedtls_ecp_keypair *prv );
+int mbedtls_ecp_check_pub_priv( const mbedtls_ecp_keypair *pub,
+ const mbedtls_ecp_keypair *prv );
#if defined(MBEDTLS_SELF_TEST)