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IABSD.fr/src/usr.bin/ssh/umac.c
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/* $OpenBSD: umac.c,v 1.20 2020/03/13 03:17:07 djm Exp $ */ /* ----------------------------------------------------------------------- * * umac.c -- C Implementation UMAC Message Authentication * * Version 0.93b of rfc4418.txt -- 2006 July 18 * * For a full description of UMAC message authentication see the UMAC * world-wide-web page at http://www.cs.ucdavis.edu/~rogaway/umac * Please report bugs and suggestions to the UMAC webpage. * * Copyright (c) 1999-2006 Ted Krovetz * * Permission to use, copy, modify, and distribute this software and * its documentation for any purpose and with or without fee, is hereby * granted provided that the above copyright notice appears in all copies * and in supporting documentation, and that the name of the copyright * holder not be used in advertising or publicity pertaining to * distribution of the software without specific, written prior permission. * * Comments should be directed to Ted Krovetz (tdk@acm.org) * * ---------------------------------------------------------------------- */ /* ////////////////////// IMPORTANT NOTES ///////////////////////////////// * * 1) This version does not work properly on messages larger than 16MB * * 2) If you set the switch to use SSE2, then all data must be 16-byte * aligned * * 3) When calling the function umac(), it is assumed that msg is in * a writable buffer of length divisible by 32 bytes. The message itself * does not have to fill the entire buffer, but bytes beyond msg may be * zeroed. * * 4) Three free AES implementations are supported by this implementation of * UMAC. Paulo Barreto's version is in the public domain and can be found * at http://www.esat.kuleuven.ac.be/~rijmen/rijndael/ (search for * "Barreto"). The only two files needed are rijndael-alg-fst.c and * rijndael-alg-fst.h. Brian Gladman's version is distributed with the GNU * Public license at http://fp.gladman.plus.com/AES/index.htm. It * includes a fast IA-32 assembly version. The OpenSSL crypo library is * the third. * * 5) With FORCE_C_ONLY flags set to 0, incorrect results are sometimes * produced under gcc with optimizations set -O3 or higher. Dunno why. * /////////////////////////////////////////////////////////////////////// */ /* ---------------------------------------------------------------------- */ /* --- User Switches ---------------------------------------------------- */ /* ---------------------------------------------------------------------- */ #ifndef UMAC_OUTPUT_LEN #define UMAC_OUTPUT_LEN 8 /* Alowable: 4, 8, 12, 16 */ #endif /* #define FORCE_C_ONLY 1 ANSI C and 64-bit integers req'd */ /* #define AES_IMPLEMENTAION 1 1 = OpenSSL, 2 = Barreto, 3 = Gladman */ /* #define SSE2 0 Is SSE2 is available? */ /* #define RUN_TESTS 0 Run basic correctness/speed tests */ /* #define UMAC_AE_SUPPORT 0 Enable authenticated encryption */ /* ---------------------------------------------------------------------- */ /* -- Global Includes --------------------------------------------------- */ /* ---------------------------------------------------------------------- */ #include <sys/types.h> #include <endian.h> #include <string.h> #include <stdarg.h> #include <stdio.h> #include <stdlib.h> #include <stddef.h> #include "xmalloc.h" #include "umac.h" #include "misc.h" /* ---------------------------------------------------------------------- */ /* --- Primitive Data Types --- */ /* ---------------------------------------------------------------------- */ /* The following assumptions may need change on your system */ typedef u_int8_t UINT8; /* 1 byte */ typedef u_int16_t UINT16; /* 2 byte */ typedef u_int32_t UINT32; /* 4 byte */ typedef u_int64_t UINT64; /* 8 bytes */ typedef unsigned int UWORD; /* Register */ /* ---------------------------------------------------------------------- */ /* --- Constants -------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ #define UMAC_KEY_LEN 16 /* UMAC takes 16 bytes of external key */ /* Message "words" are read from memory in an endian-specific manner. */ /* For this implementation to behave correctly, __LITTLE_ENDIAN__ must */ /* be set true if the host computer is little-endian. */ #if BYTE_ORDER == LITTLE_ENDIAN #define __LITTLE_ENDIAN__ 1 #else #define __LITTLE_ENDIAN__ 0 #endif /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ----- Architecture Specific ------------------------------------------ */ /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ----- Primitive Routines --------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* --- 32-bit by 32-bit to 64-bit Multiplication ------------------------ */ /* ---------------------------------------------------------------------- */ #define MUL64(a,b) ((UINT64)((UINT64)(UINT32)(a) * (UINT64)(UINT32)(b))) /* ---------------------------------------------------------------------- */ /* --- Endian Conversion --- Forcing assembly on some platforms */ /* ---------------------------------------------------------------------- */ /* The following definitions use the above reversal-primitives to do the right * thing on endian specific load and stores. */ #if BYTE_ORDER == LITTLE_ENDIAN #define LOAD_UINT32_REVERSED(p) get_u32(p) #define STORE_UINT32_REVERSED(p,v) put_u32(p,v) #else #define LOAD_UINT32_REVERSED(p) get_u32_le(p) #define STORE_UINT32_REVERSED(p,v) put_u32_le(p,v) #endif #define LOAD_UINT32_LITTLE(p) (get_u32_le(p)) #define STORE_UINT32_BIG(p,v) put_u32(p, v) /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ----- Begin KDF & PDF Section ---------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* UMAC uses AES with 16 byte block and key lengths */ #define AES_BLOCK_LEN 16 #ifdef WITH_OPENSSL #include <openssl/aes.h> typedef AES_KEY aes_int_key[1]; #define aes_encryption(in,out,int_key) \ AES_encrypt((u_char *)(in),(u_char *)(out),(AES_KEY *)int_key) #define aes_key_setup(key,int_key) \ AES_set_encrypt_key((const u_char *)(key),UMAC_KEY_LEN*8,int_key) #else #include "rijndael.h" #define AES_ROUNDS ((UMAC_KEY_LEN / 4) + 6) typedef UINT8 aes_int_key[AES_ROUNDS+1][4][4]; /* AES internal */ #define aes_encryption(in,out,int_key) \ rijndaelEncrypt((u32 *)(int_key), AES_ROUNDS, (u8 *)(in), (u8 *)(out)) #define aes_key_setup(key,int_key) \ rijndaelKeySetupEnc((u32 *)(int_key), (const unsigned char *)(key), \ UMAC_KEY_LEN*8) #endif /* The user-supplied UMAC key is stretched using AES in a counter * mode to supply all random bits needed by UMAC. The kdf function takes * an AES internal key representation 'key' and writes a stream of * 'nbytes' bytes to the memory pointed at by 'buffer_ptr'. Each distinct * 'ndx' causes a distinct byte stream. */ static void kdf(void *buffer_ptr, aes_int_key key, UINT8 ndx, int nbytes) { UINT8 in_buf[AES_BLOCK_LEN] = {0}; UINT8 out_buf[AES_BLOCK_LEN]; UINT8 *dst_buf = (UINT8 *)buffer_ptr; int i; /* Setup the initial value */ in_buf[AES_BLOCK_LEN-9] = ndx; in_buf[AES_BLOCK_LEN-1] = i = 1; while (nbytes >= AES_BLOCK_LEN) { aes_encryption(in_buf, out_buf, key); memcpy(dst_buf,out_buf,AES_BLOCK_LEN); in_buf[AES_BLOCK_LEN-1] = ++i; nbytes -= AES_BLOCK_LEN; dst_buf += AES_BLOCK_LEN; } if (nbytes) { aes_encryption(in_buf, out_buf, key); memcpy(dst_buf,out_buf,nbytes); } explicit_bzero(in_buf, sizeof(in_buf)); explicit_bzero(out_buf, sizeof(out_buf)); } /* The final UHASH result is XOR'd with the output of a pseudorandom * function. Here, we use AES to generate random output and * xor the appropriate bytes depending on the last bits of nonce. * This scheme is optimized for sequential, increasing big-endian nonces. */ typedef struct { UINT8 cache[AES_BLOCK_LEN]; /* Previous AES output is saved */ UINT8 nonce[AES_BLOCK_LEN]; /* The AES input making above cache */ aes_int_key prf_key; /* Expanded AES key for PDF */ } pdf_ctx; static void pdf_init(pdf_ctx *pc, aes_int_key prf_key) { UINT8 buf[UMAC_KEY_LEN]; kdf(buf, prf_key, 0, UMAC_KEY_LEN); aes_key_setup(buf, pc->prf_key); /* Initialize pdf and cache */ memset(pc->nonce, 0, sizeof(pc->nonce)); aes_encryption(pc->nonce, pc->cache, pc->prf_key); explicit_bzero(buf, sizeof(buf)); } static void pdf_gen_xor(pdf_ctx *pc, const UINT8 nonce[8], UINT8 buf[8]) { /* 'ndx' indicates that we'll be using the 0th or 1st eight bytes * of the AES output. If last time around we returned the ndx-1st * element, then we may have the result in the cache already. */ #if (UMAC_OUTPUT_LEN == 4) #define LOW_BIT_MASK 3 #elif (UMAC_OUTPUT_LEN == 8) #define LOW_BIT_MASK 1 #elif (UMAC_OUTPUT_LEN > 8) #define LOW_BIT_MASK 0 #endif union { UINT8 tmp_nonce_lo[4]; UINT32 align; } t; #if LOW_BIT_MASK != 0 int ndx = nonce[7] & LOW_BIT_MASK; #endif *(UINT32 *)t.tmp_nonce_lo = ((const UINT32 *)nonce)[1]; t.tmp_nonce_lo[3] &= ~LOW_BIT_MASK; /* zero last bit */ if ( (((UINT32 *)t.tmp_nonce_lo)[0] != ((UINT32 *)pc->nonce)[1]) || (((const UINT32 *)nonce)[0] != ((UINT32 *)pc->nonce)[0]) ) { ((UINT32 *)pc->nonce)[0] = ((const UINT32 *)nonce)[0]; ((UINT32 *)pc->nonce)[1] = ((UINT32 *)t.tmp_nonce_lo)[0]; aes_encryption(pc->nonce, pc->cache, pc->prf_key); } #if (UMAC_OUTPUT_LEN == 4) *((UINT32 *)buf) ^= ((UINT32 *)pc->cache)[ndx]; #elif (UMAC_OUTPUT_LEN == 8) *((UINT64 *)buf) ^= ((UINT64 *)pc->cache)[ndx]; #elif (UMAC_OUTPUT_LEN == 12) ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0]; ((UINT32 *)buf)[2] ^= ((UINT32 *)pc->cache)[2]; #elif (UMAC_OUTPUT_LEN == 16) ((UINT64 *)buf)[0] ^= ((UINT64 *)pc->cache)[0]; ((UINT64 *)buf)[1] ^= ((UINT64 *)pc->cache)[1]; #endif } /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ----- Begin NH Hash Section ------------------------------------------ */ /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* The NH-based hash functions used in UMAC are described in the UMAC paper * and specification, both of which can be found at the UMAC website. * The interface to this implementation has two * versions, one expects the entire message being hashed to be passed * in a single buffer and returns the hash result immediately. The second * allows the message to be passed in a sequence of buffers. In the * muliple-buffer interface, the client calls the routine nh_update() as * many times as necessary. When there is no more data to be fed to the * hash, the client calls nh_final() which calculates the hash output. * Before beginning another hash calculation the nh_reset() routine * must be called. The single-buffer routine, nh(), is equivalent to * the sequence of calls nh_update() and nh_final(); however it is * optimized and should be preferred whenever the multiple-buffer interface * is not necessary. When using either interface, it is the client's * responsibility to pass no more than L1_KEY_LEN bytes per hash result. * * The routine nh_init() initializes the nh_ctx data structure and * must be called once, before any other PDF routine. */ /* The "nh_aux" routines do the actual NH hashing work. They * expect buffers to be multiples of L1_PAD_BOUNDARY. These routines * produce output for all STREAMS NH iterations in one call, * allowing the parallel implementation of the streams. */ #define STREAMS (UMAC_OUTPUT_LEN / 4) /* Number of times hash is applied */ #define L1_KEY_LEN 1024 /* Internal key bytes */ #define L1_KEY_SHIFT 16 /* Toeplitz key shift between streams */ #define L1_PAD_BOUNDARY 32 /* pad message to boundary multiple */ #define ALLOC_BOUNDARY 16 /* Keep buffers aligned to this */ #define HASH_BUF_BYTES 64 /* nh_aux_hb buffer multiple */ typedef struct { UINT8 nh_key [L1_KEY_LEN + L1_KEY_SHIFT * (STREAMS - 1)]; /* NH Key */ UINT8 data [HASH_BUF_BYTES]; /* Incoming data buffer */ int next_data_empty; /* Bookkeeping variable for data buffer. */ int bytes_hashed; /* Bytes (out of L1_KEY_LEN) incorporated. */ UINT64 state[STREAMS]; /* on-line state */ } nh_ctx; #if (UMAC_OUTPUT_LEN == 4) static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen) /* NH hashing primitive. Previous (partial) hash result is loaded and * then stored via hp pointer. The length of the data pointed at by "dp", * "dlen", is guaranteed to be divisible by L1_PAD_BOUNDARY (32). Key * is expected to be endian compensated in memory at key setup. */ { UINT64 h; UWORD c = dlen / 32; UINT32 *k = (UINT32 *)kp; const UINT32 *d = (const UINT32 *)dp; UINT32 d0,d1,d2,d3,d4,d5,d6,d7; UINT32 k0,k1,k2,k3,k4,k5,k6,k7; h = *((UINT64 *)hp); do { d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1); d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3); d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5); d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7); k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3); k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7); h += MUL64((k0 + d0), (k4 + d4)); h += MUL64((k1 + d1), (k5 + d5)); h += MUL64((k2 + d2), (k6 + d6)); h += MUL64((k3 + d3), (k7 + d7)); d += 8; k += 8; } while (--c); *((UINT64 *)hp) = h; } #elif (UMAC_OUTPUT_LEN == 8) static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen) /* Same as previous nh_aux, but two streams are handled in one pass, * reading and writing 16 bytes of hash-state per call. */ { UINT64 h1,h2; UWORD c = dlen / 32; UINT32 *k = (UINT32 *)kp; const UINT32 *d = (const UINT32 *)dp; UINT32 d0,d1,d2,d3,d4,d5,d6,d7; UINT32 k0,k1,k2,k3,k4,k5,k6,k7, k8,k9,k10,k11; h1 = *((UINT64 *)hp); h2 = *((UINT64 *)hp + 1); k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3); do { d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1); d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3); d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5); d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7); k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7); k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11); h1 += MUL64((k0 + d0), (k4 + d4)); h2 += MUL64((k4 + d0), (k8 + d4)); h1 += MUL64((k1 + d1), (k5 + d5)); h2 += MUL64((k5 + d1), (k9 + d5)); h1 += MUL64((k2 + d2), (k6 + d6)); h2 += MUL64((k6 + d2), (k10 + d6)); h1 += MUL64((k3 + d3), (k7 + d7)); h2 += MUL64((k7 + d3), (k11 + d7)); k0 = k8; k1 = k9; k2 = k10; k3 = k11; d += 8; k += 8; } while (--c); ((UINT64 *)hp)[0] = h1; ((UINT64 *)hp)[1] = h2; } #elif (UMAC_OUTPUT_LEN == 12) static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen) /* Same as previous nh_aux, but two streams are handled in one pass, * reading and writing 24 bytes of hash-state per call. */ { UINT64 h1,h2,h3; UWORD c = dlen / 32; UINT32 *k = (UINT32 *)kp; const UINT32 *d = (const UINT32 *)dp; UINT32 d0,d1,d2,d3,d4,d5,d6,d7; UINT32 k0,k1,k2,k3,k4,k5,k6,k7, k8,k9,k10,k11,k12,k13,k14,k15; h1 = *((UINT64 *)hp); h2 = *((UINT64 *)hp + 1); h3 = *((UINT64 *)hp + 2); k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3); k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7); do { d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1); d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3); d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5); d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7); k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11); k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15); h1 += MUL64((k0 + d0), (k4 + d4)); h2 += MUL64((k4 + d0), (k8 + d4)); h3 += MUL64((k8 + d0), (k12 + d4)); h1 += MUL64((k1 + d1), (k5 + d5)); h2 += MUL64((k5 + d1), (k9 + d5)); h3 += MUL64((k9 + d1), (k13 + d5)); h1 += MUL64((k2 + d2), (k6 + d6)); h2 += MUL64((k6 + d2), (k10 + d6)); h3 += MUL64((k10 + d2), (k14 + d6)); h1 += MUL64((k3 + d3), (k7 + d7)); h2 += MUL64((k7 + d3), (k11 + d7)); h3 += MUL64((k11 + d3), (k15 + d7)); k0 = k8; k1 = k9; k2 = k10; k3 = k11; k4 = k12; k5 = k13; k6 = k14; k7 = k15; d += 8; k += 8; } while (--c); ((UINT64 *)hp)[0] = h1; ((UINT64 *)hp)[1] = h2; ((UINT64 *)hp)[2] = h3; } #elif (UMAC_OUTPUT_LEN == 16) static void nh_aux(void *kp, const void *dp, void *hp, UINT32 dlen) /* Same as previous nh_aux, but two streams are handled in one pass, * reading and writing 24 bytes of hash-state per call. */ { UINT64 h1,h2,h3,h4; UWORD c = dlen / 32; UINT32 *k = (UINT32 *)kp; const UINT32 *d = (const UINT32 *)dp; UINT32 d0,d1,d2,d3,d4,d5,d6,d7; UINT32 k0,k1,k2,k3,k4,k5,k6,k7, k8,k9,k10,k11,k12,k13,k14,k15, k16,k17,k18,k19; h1 = *((UINT64 *)hp); h2 = *((UINT64 *)hp + 1); h3 = *((UINT64 *)hp + 2); h4 = *((UINT64 *)hp + 3); k0 = *(k+0); k1 = *(k+1); k2 = *(k+2); k3 = *(k+3); k4 = *(k+4); k5 = *(k+5); k6 = *(k+6); k7 = *(k+7); do { d0 = LOAD_UINT32_LITTLE(d+0); d1 = LOAD_UINT32_LITTLE(d+1); d2 = LOAD_UINT32_LITTLE(d+2); d3 = LOAD_UINT32_LITTLE(d+3); d4 = LOAD_UINT32_LITTLE(d+4); d5 = LOAD_UINT32_LITTLE(d+5); d6 = LOAD_UINT32_LITTLE(d+6); d7 = LOAD_UINT32_LITTLE(d+7); k8 = *(k+8); k9 = *(k+9); k10 = *(k+10); k11 = *(k+11); k12 = *(k+12); k13 = *(k+13); k14 = *(k+14); k15 = *(k+15); k16 = *(k+16); k17 = *(k+17); k18 = *(k+18); k19 = *(k+19); h1 += MUL64((k0 + d0), (k4 + d4)); h2 += MUL64((k4 + d0), (k8 + d4)); h3 += MUL64((k8 + d0), (k12 + d4)); h4 += MUL64((k12 + d0), (k16 + d4)); h1 += MUL64((k1 + d1), (k5 + d5)); h2 += MUL64((k5 + d1), (k9 + d5)); h3 += MUL64((k9 + d1), (k13 + d5)); h4 += MUL64((k13 + d1), (k17 + d5)); h1 += MUL64((k2 + d2), (k6 + d6)); h2 += MUL64((k6 + d2), (k10 + d6)); h3 += MUL64((k10 + d2), (k14 + d6)); h4 += MUL64((k14 + d2), (k18 + d6)); h1 += MUL64((k3 + d3), (k7 + d7)); h2 += MUL64((k7 + d3), (k11 + d7)); h3 += MUL64((k11 + d3), (k15 + d7)); h4 += MUL64((k15 + d3), (k19 + d7)); k0 = k8; k1 = k9; k2 = k10; k3 = k11; k4 = k12; k5 = k13; k6 = k14; k7 = k15; k8 = k16; k9 = k17; k10 = k18; k11 = k19; d += 8; k += 8; } while (--c); ((UINT64 *)hp)[0] = h1; ((UINT64 *)hp)[1] = h2; ((UINT64 *)hp)[2] = h3; ((UINT64 *)hp)[3] = h4; } /* ---------------------------------------------------------------------- */ #endif /* UMAC_OUTPUT_LENGTH */ /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ static void nh_transform(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes) /* This function is a wrapper for the primitive NH hash functions. It takes * as argument "hc" the current hash context and a buffer which must be a * multiple of L1_PAD_BOUNDARY. The key passed to nh_aux is offset * appropriately according to how much message has been hashed already. */ { UINT8 *key; key = hc->nh_key + hc->bytes_hashed; nh_aux(key, buf, hc->state, nbytes); } /* ---------------------------------------------------------------------- */ #if (__LITTLE_ENDIAN__) static void endian_convert(void *buf, UWORD bpw, UINT32 num_bytes) /* We endian convert the keys on little-endian computers to */ /* compensate for the lack of big-endian memory reads during hashing. */ { UWORD iters = num_bytes / bpw; if (bpw == 4) { UINT32 *p = (UINT32 *)buf; do { *p = LOAD_UINT32_REVERSED(p); p++; } while (--iters); } else if (bpw == 8) { UINT32 *p = (UINT32 *)buf; UINT32 t; do { t = LOAD_UINT32_REVERSED(p+1); p[1] = LOAD_UINT32_REVERSED(p); p[0] = t; p += 2; } while (--iters); } } #define endian_convert_if_le(x,y,z) endian_convert((x),(y),(z)) #else #define endian_convert_if_le(x,y,z) do{}while(0) /* Do nothing */ #endif /* ---------------------------------------------------------------------- */ static void nh_reset(nh_ctx *hc) /* Reset nh_ctx to ready for hashing of new data */ { hc->bytes_hashed = 0; hc->next_data_empty = 0; hc->state[0] = 0; #if (UMAC_OUTPUT_LEN >= 8) hc->state[1] = 0; #endif #if (UMAC_OUTPUT_LEN >= 12) hc->state[2] = 0; #endif #if (UMAC_OUTPUT_LEN == 16) hc->state[3] = 0; #endif } /* ---------------------------------------------------------------------- */ static void nh_init(nh_ctx *hc, aes_int_key prf_key) /* Generate nh_key, endian convert and reset to be ready for hashing. */ { kdf(hc->nh_key, prf_key, 1, sizeof(hc->nh_key)); endian_convert_if_le(hc->nh_key, 4, sizeof(hc->nh_key)); nh_reset(hc); } /* ---------------------------------------------------------------------- */ static void nh_update(nh_ctx *hc, const UINT8 *buf, UINT32 nbytes) /* Incorporate nbytes of data into a nh_ctx, buffer whatever is not an */ /* even multiple of HASH_BUF_BYTES. */ { UINT32 i,j; j = hc->next_data_empty; if ((j + nbytes) >= HASH_BUF_BYTES) { if (j) { i = HASH_BUF_BYTES - j; memcpy(hc->data+j, buf, i); nh_transform(hc,hc->data,HASH_BUF_BYTES); nbytes -= i; buf += i; hc->bytes_hashed += HASH_BUF_BYTES; } if (nbytes >= HASH_BUF_BYTES) { i = nbytes & ~(HASH_BUF_BYTES - 1); nh_transform(hc, buf, i); nbytes -= i; buf += i; hc->bytes_hashed += i; } j = 0; } memcpy(hc->data + j, buf, nbytes); hc->next_data_empty = j + nbytes; } /* ---------------------------------------------------------------------- */ static void zero_pad(UINT8 *p, int nbytes) { /* Write "nbytes" of zeroes, beginning at "p" */ if (nbytes >= (int)sizeof(UWORD)) { while ((ptrdiff_t)p % sizeof(UWORD)) { *p = 0; nbytes--; p++; } while (nbytes >= (int)sizeof(UWORD)) { *(UWORD *)p = 0; nbytes -= sizeof(UWORD); p += sizeof(UWORD); } } while (nbytes) { *p = 0; nbytes--; p++; } } /* ---------------------------------------------------------------------- */ static void nh_final(nh_ctx *hc, UINT8 *result) /* After passing some number of data buffers to nh_update() for integration * into an NH context, nh_final is called to produce a hash result. If any * bytes are in the buffer hc->data, incorporate them into the * NH context. Finally, add into the NH accumulation "state" the total number * of bits hashed. The resulting numbers are written to the buffer "result". * If nh_update was never called, L1_PAD_BOUNDARY zeroes are incorporated. */ { int nh_len, nbits; if (hc->next_data_empty != 0) { nh_len = ((hc->next_data_empty + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1)); zero_pad(hc->data + hc->next_data_empty, nh_len - hc->next_data_empty); nh_transform(hc, hc->data, nh_len); hc->bytes_hashed += hc->next_data_empty; } else if (hc->bytes_hashed == 0) { nh_len = L1_PAD_BOUNDARY; zero_pad(hc->data, L1_PAD_BOUNDARY); nh_transform(hc, hc->data, nh_len); } nbits = (hc->bytes_hashed << 3); ((UINT64 *)result)[0] = ((UINT64 *)hc->state)[0] + nbits; #if (UMAC_OUTPUT_LEN >= 8) ((UINT64 *)result)[1] = ((UINT64 *)hc->state)[1] + nbits; #endif #if (UMAC_OUTPUT_LEN >= 12) ((UINT64 *)result)[2] = ((UINT64 *)hc->state)[2] + nbits; #endif #if (UMAC_OUTPUT_LEN == 16) ((UINT64 *)result)[3] = ((UINT64 *)hc->state)[3] + nbits; #endif nh_reset(hc); } /* ---------------------------------------------------------------------- */ static void nh(nh_ctx *hc, const UINT8 *buf, UINT32 padded_len, UINT32 unpadded_len, UINT8 *result) /* All-in-one nh_update() and nh_final() equivalent. * Assumes that padded_len is divisible by L1_PAD_BOUNDARY and result is * well aligned */ { UINT32 nbits; /* Initialize the hash state */ nbits = (unpadded_len << 3); ((UINT64 *)result)[0] = nbits; #if (UMAC_OUTPUT_LEN >= 8) ((UINT64 *)result)[1] = nbits; #endif #if (UMAC_OUTPUT_LEN >= 12) ((UINT64 *)result)[2] = nbits; #endif #if (UMAC_OUTPUT_LEN == 16) ((UINT64 *)result)[3] = nbits; #endif nh_aux(hc->nh_key, buf, result, padded_len); } /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ----- Begin UHASH Section -------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* UHASH is a multi-layered algorithm. Data presented to UHASH is first * hashed by NH. The NH output is then hashed by a polynomial-hash layer * unless the initial data to be hashed is short. After the polynomial- * layer, an inner-product hash is used to produce the final UHASH output. * * UHASH provides two interfaces, one all-at-once and another where data * buffers are presented sequentially. In the sequential interface, the * UHASH client calls the routine uhash_update() as many times as necessary. * When there is no more data to be fed to UHASH, the client calls * uhash_final() which * calculates the UHASH output. Before beginning another UHASH calculation * the uhash_reset() routine must be called. The all-at-once UHASH routine, * uhash(), is equivalent to the sequence of calls uhash_update() and * uhash_final(); however it is optimized and should be * used whenever the sequential interface is not necessary. * * The routine uhash_init() initializes the uhash_ctx data structure and * must be called once, before any other UHASH routine. */ /* ---------------------------------------------------------------------- */ /* ----- Constants and uhash_ctx ---------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ----- Poly hash and Inner-Product hash Constants --------------------- */ /* ---------------------------------------------------------------------- */ /* Primes and masks */ #define p36 ((UINT64)0x0000000FFFFFFFFBull) /* 2^36 - 5 */ #define p64 ((UINT64)0xFFFFFFFFFFFFFFC5ull) /* 2^64 - 59 */ #define m36 ((UINT64)0x0000000FFFFFFFFFull) /* The low 36 of 64 bits */ /* ---------------------------------------------------------------------- */ typedef struct uhash_ctx { nh_ctx hash; /* Hash context for L1 NH hash */ UINT64 poly_key_8[STREAMS]; /* p64 poly keys */ UINT64 poly_accum[STREAMS]; /* poly hash result */ UINT64 ip_keys[STREAMS*4]; /* Inner-product keys */ UINT32 ip_trans[STREAMS]; /* Inner-product translation */ UINT32 msg_len; /* Total length of data passed */ /* to uhash */ } uhash_ctx; typedef struct uhash_ctx *uhash_ctx_t; /* ---------------------------------------------------------------------- */ /* The polynomial hashes use Horner's rule to evaluate a polynomial one * word at a time. As described in the specification, poly32 and poly64 * require keys from special domains. The following implementations exploit * the special domains to avoid overflow. The results are not guaranteed to * be within Z_p32 and Z_p64, but the Inner-Product hash implementation * patches any errant values. */ static UINT64 poly64(UINT64 cur, UINT64 key, UINT64 data) { UINT32 key_hi = (UINT32)(key >> 32), key_lo = (UINT32)key, cur_hi = (UINT32)(cur >> 32), cur_lo = (UINT32)cur, x_lo, x_hi; UINT64 X,T,res; X = MUL64(key_hi, cur_lo) + MUL64(cur_hi, key_lo); x_lo = (UINT32)X; x_hi = (UINT32)(X >> 32); res = (MUL64(key_hi, cur_hi) + x_hi) * 59 + MUL64(key_lo, cur_lo); T = ((UINT64)x_lo << 32); res += T; if (res < T) res += 59; res += data; if (res < data) res += 59; return res; } /* Although UMAC is specified to use a ramped polynomial hash scheme, this * implementation does not handle all ramp levels. Because we don't handle * the ramp up to p128 modulus in this implementation, we are limited to * 2^14 poly_hash() invocations per stream (for a total capacity of 2^24 * bytes input to UMAC per tag, ie. 16MB). */ static void poly_hash(uhash_ctx_t hc, UINT32 data_in[]) { int i; UINT64 *data=(UINT64*)data_in; for (i = 0; i < STREAMS; i++) { if ((UINT32)(data[i] >> 32) == 0xfffffffful) { hc->poly_accum[i] = poly64(hc->poly_accum[i], hc->poly_key_8[i], p64 - 1); hc->poly_accum[i] = poly64(hc->poly_accum[i], hc->poly_key_8[i], (data[i] - 59)); } else { hc->poly_accum[i] = poly64(hc->poly_accum[i], hc->poly_key_8[i], data[i]); } } } /* ---------------------------------------------------------------------- */ /* The final step in UHASH is an inner-product hash. The poly hash * produces a result not necessarily WORD_LEN bytes long. The inner- * product hash breaks the polyhash output into 16-bit chunks and * multiplies each with a 36 bit key. */ static UINT64 ip_aux(UINT64 t, UINT64 *ipkp, UINT64 data) { t = t + ipkp[0] * (UINT64)(UINT16)(data >> 48); t = t + ipkp[1] * (UINT64)(UINT16)(data >> 32); t = t + ipkp[2] * (UINT64)(UINT16)(data >> 16); t = t + ipkp[3] * (UINT64)(UINT16)(data); return t; } static UINT32 ip_reduce_p36(UINT64 t) { /* Divisionless modular reduction */ UINT64 ret; ret = (t & m36) + 5 * (t >> 36); if (ret >= p36) ret -= p36; /* return least significant 32 bits */ return (UINT32)(ret); } /* If the data being hashed by UHASH is no longer than L1_KEY_LEN, then * the polyhash stage is skipped and ip_short is applied directly to the * NH output. */ static void ip_short(uhash_ctx_t ahc, UINT8 *nh_res, u_char *res) { UINT64 t; UINT64 *nhp = (UINT64 *)nh_res; t = ip_aux(0,ahc->ip_keys, nhp[0]); STORE_UINT32_BIG((UINT32 *)res+0, ip_reduce_p36(t) ^ ahc->ip_trans[0]); #if (UMAC_OUTPUT_LEN >= 8) t = ip_aux(0,ahc->ip_keys+4, nhp[1]); STORE_UINT32_BIG((UINT32 *)res+1, ip_reduce_p36(t) ^ ahc->ip_trans[1]); #endif #if (UMAC_OUTPUT_LEN >= 12) t = ip_aux(0,ahc->ip_keys+8, nhp[2]); STORE_UINT32_BIG((UINT32 *)res+2, ip_reduce_p36(t) ^ ahc->ip_trans[2]); #endif #if (UMAC_OUTPUT_LEN == 16) t = ip_aux(0,ahc->ip_keys+12, nhp[3]); STORE_UINT32_BIG((UINT32 *)res+3, ip_reduce_p36(t) ^ ahc->ip_trans[3]); #endif } /* If the data being hashed by UHASH is longer than L1_KEY_LEN, then * the polyhash stage is not skipped and ip_long is applied to the * polyhash output. */ static void ip_long(uhash_ctx_t ahc, u_char *res) { int i; UINT64 t; for (i = 0; i < STREAMS; i++) { /* fix polyhash output not in Z_p64 */ if (ahc->poly_accum[i] >= p64) ahc->poly_accum[i] -= p64; t = ip_aux(0,ahc->ip_keys+(i*4), ahc->poly_accum[i]); STORE_UINT32_BIG((UINT32 *)res+i, ip_reduce_p36(t) ^ ahc->ip_trans[i]); } } /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* Reset uhash context for next hash session */ static int uhash_reset(uhash_ctx_t pc) { nh_reset(&pc->hash); pc->msg_len = 0; pc->poly_accum[0] = 1; #if (UMAC_OUTPUT_LEN >= 8) pc->poly_accum[1] = 1; #endif #if (UMAC_OUTPUT_LEN >= 12) pc->poly_accum[2] = 1; #endif #if (UMAC_OUTPUT_LEN == 16) pc->poly_accum[3] = 1; #endif return 1; } /* ---------------------------------------------------------------------- */ /* Given a pointer to the internal key needed by kdf() and a uhash context, * initialize the NH context and generate keys needed for poly and inner- * product hashing. All keys are endian adjusted in memory so that native * loads cause correct keys to be in registers during calculation. */ static void uhash_init(uhash_ctx_t ahc, aes_int_key prf_key) { int i; UINT8 buf[(8*STREAMS+4)*sizeof(UINT64)]; /* Zero the entire uhash context */ memset(ahc, 0, sizeof(uhash_ctx)); /* Initialize the L1 hash */ nh_init(&ahc->hash, prf_key); /* Setup L2 hash variables */ kdf(buf, prf_key, 2, sizeof(buf)); /* Fill buffer with index 1 key */ for (i = 0; i < STREAMS; i++) { /* Fill keys from the buffer, skipping bytes in the buffer not * used by this implementation. Endian reverse the keys if on a * little-endian computer. */ memcpy(ahc->poly_key_8+i, buf+24*i, 8); endian_convert_if_le(ahc->poly_key_8+i, 8, 8); /* Mask the 64-bit keys to their special domain */ ahc->poly_key_8[i] &= ((UINT64)0x01ffffffu << 32) + 0x01ffffffu; ahc->poly_accum[i] = 1; /* Our polyhash prepends a non-zero word */ } /* Setup L3-1 hash variables */ kdf(buf, prf_key, 3, sizeof(buf)); /* Fill buffer with index 2 key */ for (i = 0; i < STREAMS; i++) memcpy(ahc->ip_keys+4*i, buf+(8*i+4)*sizeof(UINT64), 4*sizeof(UINT64)); endian_convert_if_le(ahc->ip_keys, sizeof(UINT64), sizeof(ahc->ip_keys)); for (i = 0; i < STREAMS*4; i++) ahc->ip_keys[i] %= p36; /* Bring into Z_p36 */ /* Setup L3-2 hash variables */ /* Fill buffer with index 4 key */ kdf(ahc->ip_trans, prf_key, 4, STREAMS * sizeof(UINT32)); endian_convert_if_le(ahc->ip_trans, sizeof(UINT32), STREAMS * sizeof(UINT32)); explicit_bzero(buf, sizeof(buf)); } /* ---------------------------------------------------------------------- */ #if 0 static uhash_ctx_t uhash_alloc(u_char key[]) { /* Allocate memory and force to a 16-byte boundary. */ uhash_ctx_t ctx; u_char bytes_to_add; aes_int_key prf_key; ctx = (uhash_ctx_t)malloc(sizeof(uhash_ctx)+ALLOC_BOUNDARY); if (ctx) { if (ALLOC_BOUNDARY) { bytes_to_add = ALLOC_BOUNDARY - ((ptrdiff_t)ctx & (ALLOC_BOUNDARY -1)); ctx = (uhash_ctx_t)((u_char *)ctx + bytes_to_add); *((u_char *)ctx - 1) = bytes_to_add; } aes_key_setup(key,prf_key); uhash_init(ctx, prf_key); } return (ctx); } #endif /* ---------------------------------------------------------------------- */ #if 0 static int uhash_free(uhash_ctx_t ctx) { /* Free memory allocated by uhash_alloc */ u_char bytes_to_sub; if (ctx) { if (ALLOC_BOUNDARY) { bytes_to_sub = *((u_char *)ctx - 1); ctx = (uhash_ctx_t)((u_char *)ctx - bytes_to_sub); } free(ctx); } return (1); } #endif /* ---------------------------------------------------------------------- */ static int uhash_update(uhash_ctx_t ctx, const u_char *input, long len) /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and * hash each one with NH, calling the polyhash on each NH output. */ { UWORD bytes_hashed, bytes_remaining; UINT64 result_buf[STREAMS]; UINT8 *nh_result = (UINT8 *)&result_buf; if (ctx->msg_len + len <= L1_KEY_LEN) { nh_update(&ctx->hash, (const UINT8 *)input, len); ctx->msg_len += len; } else { bytes_hashed = ctx->msg_len % L1_KEY_LEN; if (ctx->msg_len == L1_KEY_LEN) bytes_hashed = L1_KEY_LEN; if (bytes_hashed + len >= L1_KEY_LEN) { /* If some bytes have been passed to the hash function */ /* then we want to pass at most (L1_KEY_LEN - bytes_hashed) */ /* bytes to complete the current nh_block. */ if (bytes_hashed) { bytes_remaining = (L1_KEY_LEN - bytes_hashed); nh_update(&ctx->hash, (const UINT8 *)input, bytes_remaining); nh_final(&ctx->hash, nh_result); ctx->msg_len += bytes_remaining; poly_hash(ctx,(UINT32 *)nh_result); len -= bytes_remaining; input += bytes_remaining; } /* Hash directly from input stream if enough bytes */ while (len >= L1_KEY_LEN) { nh(&ctx->hash, (const UINT8 *)input, L1_KEY_LEN, L1_KEY_LEN, nh_result); ctx->msg_len += L1_KEY_LEN; len -= L1_KEY_LEN; input += L1_KEY_LEN; poly_hash(ctx,(UINT32 *)nh_result); } } /* pass remaining < L1_KEY_LEN bytes of input data to NH */ if (len) { nh_update(&ctx->hash, (const UINT8 *)input, len); ctx->msg_len += len; } } return (1); } /* ---------------------------------------------------------------------- */ static int uhash_final(uhash_ctx_t ctx, u_char *res) /* Incorporate any pending data, pad, and generate tag */ { UINT64 result_buf[STREAMS]; UINT8 *nh_result = (UINT8 *)&result_buf; if (ctx->msg_len > L1_KEY_LEN) { if (ctx->msg_len % L1_KEY_LEN) { nh_final(&ctx->hash, nh_result); poly_hash(ctx,(UINT32 *)nh_result); } ip_long(ctx, res); } else { nh_final(&ctx->hash, nh_result); ip_short(ctx,nh_result, res); } uhash_reset(ctx); return (1); } /* ---------------------------------------------------------------------- */ #if 0 static int uhash(uhash_ctx_t ahc, u_char *msg, long len, u_char *res) /* assumes that msg is in a writable buffer of length divisible by */ /* L1_PAD_BOUNDARY. Bytes beyond msg[len] may be zeroed. */ { UINT8 nh_result[STREAMS*sizeof(UINT64)]; UINT32 nh_len; int extra_zeroes_needed; /* If the message to be hashed is no longer than L1_HASH_LEN, we skip * the polyhash. */ if (len <= L1_KEY_LEN) { if (len == 0) /* If zero length messages will not */ nh_len = L1_PAD_BOUNDARY; /* be seen, comment out this case */ else nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1)); extra_zeroes_needed = nh_len - len; zero_pad((UINT8 *)msg + len, extra_zeroes_needed); nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result); ip_short(ahc,nh_result, res); } else { /* Otherwise, we hash each L1_KEY_LEN chunk with NH, passing the NH * output to poly_hash(). */ do { nh(&ahc->hash, (UINT8 *)msg, L1_KEY_LEN, L1_KEY_LEN, nh_result); poly_hash(ahc,(UINT32 *)nh_result); len -= L1_KEY_LEN; msg += L1_KEY_LEN; } while (len >= L1_KEY_LEN); if (len) { nh_len = ((len + (L1_PAD_BOUNDARY - 1)) & ~(L1_PAD_BOUNDARY - 1)); extra_zeroes_needed = nh_len - len; zero_pad((UINT8 *)msg + len, extra_zeroes_needed); nh(&ahc->hash, (UINT8 *)msg, nh_len, len, nh_result); poly_hash(ahc,(UINT32 *)nh_result); } ip_long(ahc, res); } uhash_reset(ahc); return 1; } #endif /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ----- Begin UMAC Section --------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* The UMAC interface has two interfaces, an all-at-once interface where * the entire message to be authenticated is passed to UMAC in one buffer, * and a sequential interface where the message is presented a little at a * time. The all-at-once is more optimaized than the sequential version and * should be preferred when the sequential interface is not required. */ struct umac_ctx { uhash_ctx hash; /* Hash function for message compression */ pdf_ctx pdf; /* PDF for hashed output */ void *free_ptr; /* Address to free this struct via */ } umac_ctx; /* ---------------------------------------------------------------------- */ #if 0 int umac_reset(struct umac_ctx *ctx) /* Reset the hash function to begin a new authentication. */ { uhash_reset(&ctx->hash); return (1); } #endif /* ---------------------------------------------------------------------- */ int umac_delete(struct umac_ctx *ctx) /* Deallocate the ctx structure */ { if (ctx) { if (ALLOC_BOUNDARY) ctx = (struct umac_ctx *)ctx->free_ptr; freezero(ctx, sizeof(*ctx) + ALLOC_BOUNDARY); } return (1); } /* ---------------------------------------------------------------------- */ struct umac_ctx *umac_new(const u_char key[]) /* Dynamically allocate a umac_ctx struct, initialize variables, * generate subkeys from key. Align to 16-byte boundary. */ { struct umac_ctx *ctx, *octx; size_t bytes_to_add; aes_int_key prf_key; octx = ctx = xcalloc(1, sizeof(*ctx) + ALLOC_BOUNDARY); if (ctx) { if (ALLOC_BOUNDARY) { bytes_to_add = ALLOC_BOUNDARY - ((ptrdiff_t)ctx & (ALLOC_BOUNDARY - 1)); ctx = (struct umac_ctx *)((u_char *)ctx + bytes_to_add); } ctx->free_ptr = octx; aes_key_setup(key, prf_key); pdf_init(&ctx->pdf, prf_key); uhash_init(&ctx->hash, prf_key); explicit_bzero(prf_key, sizeof(prf_key)); } return (ctx); } /* ---------------------------------------------------------------------- */ int umac_final(struct umac_ctx *ctx, u_char tag[], const u_char nonce[8]) /* Incorporate any pending data, pad, and generate tag */ { uhash_final(&ctx->hash, (u_char *)tag); pdf_gen_xor(&ctx->pdf, (const UINT8 *)nonce, (UINT8 *)tag); return (1); } /* ---------------------------------------------------------------------- */ int umac_update(struct umac_ctx *ctx, const u_char *input, long len) /* Given len bytes of data, we parse it into L1_KEY_LEN chunks and */ /* hash each one, calling the PDF on the hashed output whenever the hash- */ /* output buffer is full. */ { uhash_update(&ctx->hash, input, len); return (1); } /* ---------------------------------------------------------------------- */ #if 0 int umac(struct umac_ctx *ctx, u_char *input, long len, u_char tag[], u_char nonce[8]) /* All-in-one version simply calls umac_update() and umac_final(). */ { uhash(&ctx->hash, input, len, (u_char *)tag); pdf_gen_xor(&ctx->pdf, (UINT8 *)nonce, (UINT8 *)tag); return (1); } #endif /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ----- End UMAC Section ----------------------------------------------- */ /* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */