BeRTOS
sha1.c
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00001 
00037 /*
00038  * Derived from:
00039  * SHA-1 in C
00040  * By Steve Reid <steve@edmweb.com>
00041  * 100% Public Domain
00042  */
00043 
00044 /* #define LITTLE_ENDIAN * This should be #define'd if true. */
00045 /* #define SHA1HANDSOFF * Copies data before messing with it. */
00046 
00047 #include "sha1.h"
00048 
00049 #include <cfg/compiler.h>
00050 #include <cfg/debug.h>
00051 #include <cfg/macros.h>
00052 #include <cpu/byteorder.h>  // CPU_BYTE_ORDER
00053 #include <string.h>
00054 #include <stdlib.h>
00055 #include <sec/util.h>
00056 
00057 #define SHA1_BLOCK_LEN          64
00058 #define SHA1_DIGEST_LEN         20
00059 
00060 static void SHA1Transform(uint32_t state[5], const uint8_t buffer[64]);
00061 
00062 #define rol(value, bits)  ROTL(value, bits)
00063 
00064 /* blk0() and blk() perform the initial expand. */
00065 /* I got the idea of expanding during the round function from SSLeay */
00066 #define blk0(i) (block[i] = be32_to_cpu(block[i]))
00067 #define blk(i) (block[i&15] = rol(block[(i+13)&15]^block[(i+8)&15] \
00068                                      ^block[(i+2)&15]^block[i&15],1))
00069 
00070 /* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
00071 #define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
00072 #define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
00073 #define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
00074 #define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
00075 #define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
00076 
00077 
00078 /* Hash a single 512-bit block. This is the core of the algorithm. */
00079 static void SHA1Transform(uint32_t state[5], const uint8_t buffer[64])
00080 {
00081     uint32_t a, b, c, d, e;
00082     uint32_t block[16];
00083 
00084     memcpy(&block, buffer, 64);
00085 
00086     /* Copy context->state[] to working vars */
00087     a = state[0];
00088     b = state[1];
00089     c = state[2];
00090     d = state[3];
00091     e = state[4];
00092     /* 4 rounds of 20 operations each. Loop unrolled. */
00093     R0(a,b,c,d,e, 0);
00094     R0(e,a,b,c,d, 1);
00095     R0(d,e,a,b,c, 2);
00096     R0(c,d,e,a,b, 3);
00097     R0(b,c,d,e,a, 4);
00098     R0(a,b,c,d,e, 5);
00099     R0(e,a,b,c,d, 6);
00100     R0(d,e,a,b,c, 7);
00101     R0(c,d,e,a,b, 8);
00102     R0(b,c,d,e,a, 9);
00103     R0(a,b,c,d,e,10);
00104     R0(e,a,b,c,d,11);
00105     R0(d,e,a,b,c,12);
00106     R0(c,d,e,a,b,13);
00107     R0(b,c,d,e,a,14);
00108     R0(a,b,c,d,e,15);
00109     R1(e,a,b,c,d,16);
00110     R1(d,e,a,b,c,17);
00111     R1(c,d,e,a,b,18);
00112     R1(b,c,d,e,a,19);
00113     R2(a,b,c,d,e,20);
00114     R2(e,a,b,c,d,21);
00115     R2(d,e,a,b,c,22);
00116     R2(c,d,e,a,b,23);
00117     R2(b,c,d,e,a,24);
00118     R2(a,b,c,d,e,25);
00119     R2(e,a,b,c,d,26);
00120     R2(d,e,a,b,c,27);
00121     R2(c,d,e,a,b,28);
00122     R2(b,c,d,e,a,29);
00123     R2(a,b,c,d,e,30);
00124     R2(e,a,b,c,d,31);
00125     R2(d,e,a,b,c,32);
00126     R2(c,d,e,a,b,33);
00127     R2(b,c,d,e,a,34);
00128     R2(a,b,c,d,e,35);
00129     R2(e,a,b,c,d,36);
00130     R2(d,e,a,b,c,37);
00131     R2(c,d,e,a,b,38);
00132     R2(b,c,d,e,a,39);
00133     R3(a,b,c,d,e,40);
00134     R3(e,a,b,c,d,41);
00135     R3(d,e,a,b,c,42);
00136     R3(c,d,e,a,b,43);
00137     R3(b,c,d,e,a,44);
00138     R3(a,b,c,d,e,45);
00139     R3(e,a,b,c,d,46);
00140     R3(d,e,a,b,c,47);
00141     R3(c,d,e,a,b,48);
00142     R3(b,c,d,e,a,49);
00143     R3(a,b,c,d,e,50);
00144     R3(e,a,b,c,d,51);
00145     R3(d,e,a,b,c,52);
00146     R3(c,d,e,a,b,53);
00147     R3(b,c,d,e,a,54);
00148     R3(a,b,c,d,e,55);
00149     R3(e,a,b,c,d,56);
00150     R3(d,e,a,b,c,57);
00151     R3(c,d,e,a,b,58);
00152     R3(b,c,d,e,a,59);
00153     R4(a,b,c,d,e,60);
00154     R4(e,a,b,c,d,61);
00155     R4(d,e,a,b,c,62);
00156     R4(c,d,e,a,b,63);
00157     R4(b,c,d,e,a,64);
00158     R4(a,b,c,d,e,65);
00159     R4(e,a,b,c,d,66);
00160     R4(d,e,a,b,c,67);
00161     R4(c,d,e,a,b,68);
00162     R4(b,c,d,e,a,69);
00163     R4(a,b,c,d,e,70);
00164     R4(e,a,b,c,d,71);
00165     R4(d,e,a,b,c,72);
00166     R4(c,d,e,a,b,73);
00167     R4(b,c,d,e,a,74);
00168     R4(a,b,c,d,e,75);
00169     R4(e,a,b,c,d,76);
00170     R4(d,e,a,b,c,77);
00171     R4(c,d,e,a,b,78);
00172     R4(b,c,d,e,a,79);
00173     /* Add the working vars back into context.state[] */
00174     state[0] += a;
00175     state[1] += b;
00176     state[2] += c;
00177     state[3] += d;
00178     state[4] += e;
00179     /* Wipe variables */
00180     a = b = c = d = e = 0;
00181 }
00182 
00183 static void SHA1_begin(Hash* h)
00184 {
00185     SHA1_Context *context = (SHA1_Context*)h;
00186     /* SHA1 initialization constants */
00187     context->state[0] = 0x67452301;
00188     context->state[1] = 0xEFCDAB89;
00189     context->state[2] = 0x98BADCFE;
00190     context->state[3] = 0x10325476;
00191     context->state[4] = 0xC3D2E1F0;
00192     context->count[0] = context->count[1] = 0;
00193 }
00194 
00195 /* Run your data through this. */
00196 
00197 static void SHA1_update(Hash* h, const void* vdata, size_t len)
00198 {
00199     SHA1_Context *context = (SHA1_Context*)h;
00200     const uint8_t *data = (const uint8_t*)vdata;
00201     size_t i, j;
00202 
00203     j = (context->count[0] >> 3) & 63;
00204     if ((context->count[0] += len << 3) < (len << 3))
00205         context->count[1]++;
00206     context->count[1] += (len >> 29);
00207     if ((j + len) > 63) {
00208         memcpy(&context->buffer[j], data, (i = 64-j));
00209         SHA1Transform(context->state, context->buffer);
00210         for ( ; i + 63 < len; i += 64) {
00211             SHA1Transform(context->state, &data[i]);
00212         }
00213         j = 0;
00214     } else
00215         i = 0;
00216     memcpy(&context->buffer[j], &data[i], len - i);
00217 }
00218 
00219 
00220 /* Add padding and return the message digest. */
00221 
00222 static uint8_t *SHA1_final(Hash* h)
00223 {
00224     SHA1_Context *context = (SHA1_Context*)h;
00225     uint32_t i;
00226     uint8_t finalcount[8];
00227 
00228     for (i = 0; i < 8; i++)
00229         finalcount[i] = (uint8_t)((context->count[(i >= 4 ? 0 : 1)]
00230                                    >> ((3-(i & 3)) * 8) ) & 255);  /* Endian independent */
00231 
00232     SHA1_update(h, "\200", 1);
00233     while ((context->count[0] & 504) != 448)
00234         SHA1_update(h, "\0", 1);
00235     SHA1_update(h, finalcount, 8);  /* Should cause a SHA1Transform() */
00236 
00237     for (i = 0; i < 20; i++)
00238         context->buffer[i] = (uint8_t)
00239                              ((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
00240 
00241     PURGE(i);
00242     PURGE(finalcount);
00243     return context->buffer;
00244 }
00245 
00246 
00247 /*************************************************************/
00248 
00249 void SHA1_init(SHA1_Context* ctx)
00250 {
00251     ctx->h.block_len = SHA1_BLOCK_LEN;
00252     ctx->h.digest_len = SHA1_DIGEST_LEN;
00253     ctx->h.begin = SHA1_begin;
00254     ctx->h.update = SHA1_update;
00255     ctx->h.final = SHA1_final;
00256 }