t_cose_sign1_verify.h

Go to the documentation of this file.

/*
 *  t_cose_sign1_verify.h
 *
 * Copyright 2019-2021, Laurence Lundblade
 *
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * See BSD-3-Clause license in README.md
 */
 
 
#ifndef __T_COSE_SIGN1_VERIFY_H__
#define __T_COSE_SIGN1_VERIFY_H__
 
#include <stdint.h>
#include <stdbool.h>
#include "t_cose/q_useful_buf.h"
#include "t_cose/t_cose_common.h"
#include "qcbor/qcbor_common.h"
 
#ifdef __cplusplus
extern "C" {
#if 0
} /* Keep editor indention formatting happy */
#endif
#endif
 
#ifndef QCBOR_SPIFFY_DECODE
#error This version of t_cose requires a version of QCBOR that supports spiffy decode
#endif
 
struct t_cose_parameters {
    int32_t               cose_algorithm_id;
 
    struct q_useful_buf_c kid;
 
    struct q_useful_buf_c iv;
 
    struct q_useful_buf_c partial_iv;
 
#ifndef T_COSE_DISABLE_CONTENT_TYPE
    struct q_useful_buf_c content_type_tstr;
 
    uint32_t              content_type_uint;
#endif /* T_COSE_DISABLE_CONTENT_TYPE */
};
 
 
#define T_COSE_UNSET_ALGORITHM_ID 0
 
 
 
 
#define T_COSE_OPT_ALLOW_SHORT_CIRCUIT 0x00000001
 
 
#define T_COSE_OPT_REQUIRE_KID 0x00000002
 
 
#define T_COSE_OPT_TAG_REQUIRED  0x00000004
 
 
#define T_COSE_OPT_TAG_PROHIBITED  0x00000010
 
 
#define T_COSE_OPT_DECODE_ONLY  0x00000008
 
 
#define T_COSE_OPT_UNKNOWN_CRIT_ALLOWED  0x00000020
 
 
#define T_COSE_MAX_TAGS_TO_RETURN 4
 
 
struct t_cose_sign1_verify_ctx {
    /* Private data structure */
    struct t_cose_key     verification_key;
    uint32_t              option_flags;
    uint64_t              auTags[T_COSE_MAX_TAGS_TO_RETURN];
 
#ifndef T_COSE_DISABLE_EDDSA
    struct q_useful_buf  auxiliary_buffer;
 
    /* The size of the serialized Sig_Structure used in the last
     * verification. This can be used by the user to determine a
     * suitable auxiliary buffer size.
     */
    size_t               auxiliary_buffer_size;
#endif
};
 
 
static void
t_cose_sign1_verify_init(struct t_cose_sign1_verify_ctx *context,
                         uint32_t                        option_flags);
 
 
static void
t_cose_sign1_set_verification_key(struct t_cose_sign1_verify_ctx *context,
                                  struct t_cose_key               verification_key);
 
 
static void
t_cose_sign1_verify_set_auxiliary_buffer(struct t_cose_sign1_verify_ctx *context,
                                         struct q_useful_buf             auxiliary_buffer);
 
static size_t
t_cose_sign1_verify_auxiliary_buffer_size(struct t_cose_sign1_verify_ctx *context);
 
static enum t_cose_err_t
t_cose_sign1_verify(struct t_cose_sign1_verify_ctx *context,
                    struct q_useful_buf_c           sign1,
                    struct q_useful_buf_c          *payload,
                    struct t_cose_parameters       *parameters);
 
 
static enum t_cose_err_t
t_cose_sign1_verify_aad(struct t_cose_sign1_verify_ctx *context,
                        struct q_useful_buf_c           sign1,
                        struct q_useful_buf_c           aad,
                        struct q_useful_buf_c          *payload,
                        struct t_cose_parameters       *parameters);
 
 
static inline enum t_cose_err_t
t_cose_sign1_verify_detached(struct t_cose_sign1_verify_ctx *context,
                             struct q_useful_buf_c           cose_sign1,
                             struct q_useful_buf_c           aad,
                             struct q_useful_buf_c           detached_payload,
                             struct t_cose_parameters       *parameters);
 
 
static uint64_t
t_cose_sign1_get_nth_tag(const struct t_cose_sign1_verify_ctx *context,
                         size_t                                n);
 
 
 
 
/* ------------------------------------------------------------------------
 * Inline implementations of public functions defined above.
 */
static inline void
t_cose_sign1_verify_init(struct t_cose_sign1_verify_ctx *me,
                         uint32_t                        option_flags)
{
    memset(me, 0, sizeof(*me));
    me->option_flags = option_flags;
 
#ifndef T_COSE_DISABLE_EDDSA
    /* Start with large (but NULL) auxiliary buffer. If EdDSA is used,
     * the Sig_Structure data will be serialized here.
     */
    me->auxiliary_buffer.len = SIZE_MAX;
#endif
}
 
 
static inline void
t_cose_sign1_set_verification_key(struct t_cose_sign1_verify_ctx *me,
                                  struct t_cose_key               verification_key)
{
    me->verification_key = verification_key;
}
 
static inline void
t_cose_sign1_verify_set_auxiliary_buffer(struct t_cose_sign1_verify_ctx *me,
                                         struct q_useful_buf             auxiliary_buffer)
{
#ifndef T_COSE_DISABLE_EDDSA
    me->auxiliary_buffer = auxiliary_buffer;
#else
    (void)me;
    (void)auxiliary_buffer;
#endif
}
 
static inline size_t
t_cose_sign1_verify_auxiliary_buffer_size(struct t_cose_sign1_verify_ctx *me)
{
#ifndef T_COSE_DISABLE_EDDSA
    return me->auxiliary_buffer_size;
#else
    /* If EdDSA is disabled we don't ever need an auxiliary buffer. */
    (void)me;
    return 0;
#endif
}
 
 
static inline uint64_t
t_cose_sign1_get_nth_tag(const struct t_cose_sign1_verify_ctx *context,
                         size_t                                n)
{
    if(n > T_COSE_MAX_TAGS_TO_RETURN) {
        return CBOR_TAG_INVALID64;
    }
    return context->auTags[n];
}
 
 
enum t_cose_err_t
t_cose_sign1_verify_internal(struct t_cose_sign1_verify_ctx *me,
                             struct q_useful_buf_c           sign1,
                             struct q_useful_buf_c           aad,
                             struct q_useful_buf_c          *payload,
                             struct t_cose_parameters       *parameters,
                             bool                            is_detached);
 
 
static inline enum t_cose_err_t
t_cose_sign1_verify(struct t_cose_sign1_verify_ctx *me,
                    struct q_useful_buf_c           sign1,
                    struct q_useful_buf_c          *payload,
                    struct t_cose_parameters       *parameters)
{
    return t_cose_sign1_verify_internal(me,
                                        sign1,
                                        NULL_Q_USEFUL_BUF_C,
                                        payload,
                                        parameters,
                                        false);
}
 
 
static inline enum t_cose_err_t
t_cose_sign1_verify_aad(struct t_cose_sign1_verify_ctx *me,
                        struct q_useful_buf_c           cose_sign1,
                        struct q_useful_buf_c           aad,
                        struct q_useful_buf_c          *payload,
                        struct t_cose_parameters       *parameters)
{
     return t_cose_sign1_verify_internal(me,
                                         cose_sign1,
                                         aad,
                                         payload,
                                         parameters,
                                         false);
}
 
 
static inline enum t_cose_err_t
t_cose_sign1_verify_detached(struct t_cose_sign1_verify_ctx *me,
                             struct q_useful_buf_c           cose_sign1,
                             struct q_useful_buf_c           aad,
                             struct q_useful_buf_c           detached_payload,
                             struct t_cose_parameters       *parameters)
{
     return t_cose_sign1_verify_internal(me,
                                         cose_sign1,
                                         aad,
                                         &detached_payload,
                                         parameters,
                                         true);
}
 
#ifdef __cplusplus
}
#endif
 
#endif /* __T_COSE_SIGN1_VERIFY_H__ */