diff options
Diffstat (limited to 'toys')
| -rw-r--r-- | toys/sha1.c | 121 |
1 files changed, 57 insertions, 64 deletions
diff --git a/toys/sha1.c b/toys/sha1.c index 4180f39c..b57805f9 100644 --- a/toys/sha1.c +++ b/toys/sha1.c @@ -13,12 +13,15 @@ struct sha1 { uint32_t state[5]; - uint32_t count[2]; - unsigned char buffer[64]; + uint64_t count; + union { + unsigned char c[64]; + uint32_t i[16]; + } buffer; }; void sha1_init(struct sha1 *this); -void sha1_transform(unsigned int state[5], unsigned char buffer[64]); +void sha1_transform(struct sha1 *this); void sha1_update(struct sha1 *this, unsigned char *data, unsigned int len); void sha1_final(struct sha1 *this, unsigned char digest[20]); @@ -27,13 +30,13 @@ void sha1_final(struct sha1 *this, unsigned char digest[20]); /* blk0() and blk() perform the initial expand. */ /* I got the idea of expanding during the round function from SSLeay */ #ifdef LITTLE_ENDIAN -#define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \ - |(rol(block->l[i],8)&0x00FF00FF)) +#define blk0(i) (block[i] = (rol(block[i],24)&0xFF00FF00) \ + |(rol(block[i],8)&0x00FF00FF)) #else -#define blk0(i) block->l[i] +#define blk0(i) block[i] #endif -#define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \ - ^block->l[(i+2)&15]^block->l[i&15],1)) +#define blk(i) (block[i&15] = rol(block[(i+13)&15]^block[(i+8)&15] \ + ^block[(i+2)&15]^block[i&15],1)) /* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */ #define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30); @@ -52,25 +55,17 @@ void printy(unsigned char *this) /* Hash a single 512-bit block. This is the core of the algorithm. */ -void sha1_transform(unsigned int state[5], unsigned char buffer[64]) +void sha1_transform(struct sha1 *this) { unsigned int a, b, c, d, e; - - typedef union { - unsigned char c[64]; - unsigned int l[16]; - } CHAR64LONG16; - CHAR64LONG16* block; - unsigned char workspace[64]; - block = (CHAR64LONG16*)workspace; - memcpy(block, buffer, 64); + uint32_t *block = this->buffer.i; /* Copy context->state[] to working vars */ - a = state[0]; - b = state[1]; - c = state[2]; - d = state[3]; - e = state[4]; + a = this->state[0]; + b = this->state[1]; + c = this->state[2]; + d = this->state[3]; + e = this->state[4]; /* 4 rounds of 20 operations each. Loop unrolled. */ R0(a,b,c,d,e, 0); R0(e,a,b,c,d, 1); R0(d,e,a,b,c, 2); R0(c,d,e,a,b, 3); R0(b,c,d,e,a, 4); R0(a,b,c,d,e, 5); R0(e,a,b,c,d, 6); R0(d,e,a,b,c, 7); @@ -93,12 +88,12 @@ void sha1_transform(unsigned int state[5], unsigned char buffer[64]) R4(d,e,a,b,c,72); R4(c,d,e,a,b,73); R4(b,c,d,e,a,74); R4(a,b,c,d,e,75); R4(e,a,b,c,d,76); R4(d,e,a,b,c,77); R4(c,d,e,a,b,78); R4(b,c,d,e,a,79); /* Add the working vars back into context.state[] */ - state[0] += a; - state[1] += b; - state[2] += c; - state[3] += d; - state[4] += e; - + this->state[0] += a; + this->state[1] += b; + this->state[2] += c; + this->state[3] += d; + this->state[4] += e; +printy(this->state); /* Wipe variables */ a = b = c = d = e = 0; } @@ -114,7 +109,7 @@ void sha1_init(struct sha1 *this) this->state[2] = 0x98BADCFE; this->state[3] = 0x10325476; this->state[4] = 0xC3D2E1F0; - this->count[0] = this->count[1] = 0; + this->count = 0; } /* Run your data through this function. */ @@ -123,49 +118,52 @@ void sha1_update(struct sha1 *this, unsigned char *data, unsigned int len) { unsigned int i, j; - j = (this->count[0] >> 3) & 63; - if ((this->count[0] += len << 3) < (len << 3)) this->count[1]++; - this->count[1] += (len >> 29); + j = this->count & 63; + this->count += len; + + // Enough data to process a frame? if ((j + len) > 63) { - memcpy(this->buffer + j, data, (i = 64-j)); - sha1_transform(this->state, this->buffer); - for ( ; i + 63 < len; i += 64) - sha1_transform(this->state, data + i); + i = 64-j; + memcpy(this->buffer.c + j, data, i); + sha1_transform(this); + for ( ; i + 63 < len; i += 64) { + memcpy(this->buffer.c, data + i, 64); + sha1_transform(this); + } j = 0; - } - else i = 0; - memcpy(this->buffer + j, data + i, len - i); + } else i = 0; + // Grab remaining chunk + memcpy(this->buffer.c + j, data + i, len - i); } - /* Add padding and return the message digest. */ void sha1_final(struct sha1 *this, unsigned char digest[20]) { - unsigned int i, j; - unsigned char finalcount[8]; + uint64_t count = this->count << 3; + unsigned int i; + unsigned char buf; + + // End the message by appending a "1" bit to the data, ending with the + // message size (in bits, big endian), and adding enough zero bits in + // between to pad to the end of the next 64-byte frame. Since our input + // up to now has been in whole bytes, we can deal with bytes here too. + + buf = 0x80; + do { + sha1_update(this, &buf, 1); + buf = 0; + } while ((this->count & 63) != 56); + for (i = 0; i < 8; i++) + this->buffer.c[56+i] = count >> (8*(7-i)); + sha1_transform(this); - for (i = 0; i < 8; i++) { - finalcount[i] = (unsigned char)((this->count[(i >= 4 ? 0 : 1)] - >> ((3-(i & 3)) * 8) ) & 255); /* Endian independent */ - } - sha1_update(this, (unsigned char *)"\200", 1); - while ((this->count[0] & 504) != 448) { - sha1_update(this, (unsigned char *)"\0", 1); - } - sha1_update(this, finalcount, 8); /* Should cause a SHA1Transform() */ for (i = 0; i < 20; i++) { digest[i] = (unsigned char) ((this->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255); } /* Wipe variables */ - i = j = 0; - memset(this->buffer, 0, 64); - memset(this->state, 0, 20); - memset(this->count, 0, 8); - memset(finalcount, 0, 8); - /* make SHA1Transform overwrite it's own static vars */ - sha1_transform(this->state, this->buffer); + i = 0; } @@ -179,11 +177,6 @@ int main(int argc, char** argv) unsigned char digest[20], buffer[16384]; FILE* file; - if (argc > 2) { - puts("Public domain SHA-1 implementation - by Steve Reid <steve@edmweb.com>"); - puts("Produces the SHA-1 hash of a file, or stdin if no file is specified."); - exit(0); - } if (argc < 2) { file = stdin; } |