| Quellcodebibliothek Statistik Leitseite products/sources/formale Sprachen/C/Linux/crypto/ (Open Source Betriebssystem Version 6.17.9©) Datei vom 24.10.2025 mit Größe 3 kB |
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Quelle dh_helper.c Sprache: C |
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// SPDX-License-Identifier: GPL-2.0-or-later
/* * Copyright (c) 2016, Intel Corporation * Authors: Salvatore Benedetto <salvatore.benedetto@intel.com> */ #include <linux/kernel.h> #include <linux/export.h> #include <linux/err.h> #include <linux/string.h> #include <crypto/dh.h> #include <crypto/kpp.h> #define DH_KPP_SECRET_MIN_SIZE (sizeof(struct kpp_secret) + 3 * sizeof(int)) static inline u8 *dh_pack_data(u8 *dst, u8 *end, const void *src, size_t size) { if (!dst || size > end - dst) return NULL; memcpy(dst, src, size); return dst + size; } static inline const u8 *dh_unpack_data(void *dst, const void *src, size_t size) { memcpy(dst, src, size); return src + size; } static inline unsigned int dh_data_size(const struct dh *p) { return p->key_size + p->p_size + p->g_size; } unsigned int crypto_dh_key_len(const struct dh *p) { return DH_KPP_SECRET_MIN_SIZE + dh_data_size(p); } EXPORT_SYMBOL_GPL(crypto_dh_key_len); int crypto_dh_encode_key(char *buf, unsigned int len, const struct dh *params) { u8 *ptr = buf; u8 * const end = ptr + len; struct kpp_secret secret = { .type = CRYPTO_KPP_SECRET_TYPE_DH, .len = len }; if (unlikely(!len)) return -EINVAL; ptr = dh_pack_data(ptr, end, &secret, sizeof(secret)); ptr = dh_pack_data(ptr, end, ¶ms->key_size, sizeof(params->key_size)); ptr = dh_pack_data(ptr, end, ¶ms->p_size, sizeof(params->p_size)); ptr = dh_pack_data(ptr, end, ¶ms->g_size, sizeof(params->g_size)); ptr = dh_pack_data(ptr, end, params->key, params->key_size); ptr = dh_pack_data(ptr, end, params->p, params->p_size); ptr = dh_pack_data(ptr, end, params->g, params->g_size); if (ptr != end) return -EINVAL; return 0; } EXPORT_SYMBOL_GPL(crypto_dh_encode_key); int __crypto_dh_decode_key(const char *buf, unsigned int len, struct dh *params) { const u8 *ptr = buf; struct kpp_secret secret; if (unlikely(!buf || len < DH_KPP_SECRET_MIN_SIZE)) return -EINVAL; ptr = dh_unpack_data(&secret, ptr, sizeof(secret)); if (secret.type != CRYPTO_KPP_SECRET_TYPE_DH) return -EINVAL; ptr = dh_unpack_data(¶ms->key_size, ptr, sizeof(params->key_size)); ptr = dh_unpack_data(¶ms->p_size, ptr, sizeof(params->p_size)); ptr = dh_unpack_data(¶ms->g_size, ptr, sizeof(params->g_size)); if (secret.len != crypto_dh_key_len(params)) return -EINVAL; /* Don't allocate memory. Set pointers to data within * the given buffer */ params->key = (void *)ptr; params->p = (void *)(ptr + params->key_size); params->g = (void *)(ptr + params->key_size + params->p_size); return 0; } int crypto_dh_decode_key(const char *buf, unsigned int len, struct dh *params) { int err; err = __crypto_dh_decode_key(buf, len, params); if (err) return err; /* * Don't permit the buffer for 'key' or 'g' to be larger than 'p', since * some drivers assume otherwise. */ if (params->key_size > params->p_size || params->g_size > params->p_size) return -EINVAL; /* * Don't permit 'p' to be 0. It's not a prime number, and it's subject * to corner cases such as 'mod 0' being undefined or * crypto_kpp_maxsize() returning 0. */ if (memchr_inv(params->p, 0, params->p_size) == NULL) return -EINVAL; return 0; } EXPORT_SYMBOL_GPL(crypto_dh_decode_key); ¤ Dauer der Verarbeitung: 0.3 Sekunden ¤*© Formatika GbR, Deutschland |
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2026-03-28