X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=blobdiff_plain;f=sshblowf.c;h=353116a6604fdc8334d774f4004999e934f9d321;hb=510f49e405e71ba5c97875e7a019364e1ef5fac9;hp=e3b4f509c13d1297ef7405c29a263d607144029a;hpb=fe83afa6ec32532531ddc9730bd85b370242c740;p=PuTTY.git diff --git a/sshblowf.c b/sshblowf.c index e3b4f509..353116a6 100644 --- a/sshblowf.c +++ b/sshblowf.c @@ -7,15 +7,37 @@ #include #include #include "ssh.h" +#include "sshblowf.h" -typedef struct { +struct BlowfishContext { word32 S0[256], S1[256], S2[256], S3[256], P[18]; word32 iv0, iv1; /* for CBC mode */ -} BlowfishContext; +}; /* * The Blowfish init data: hex digits of the fractional part of pi. * (ie pi as a hex fraction is 3.243F6A8885A308D3...) + * + * If you have Simon Tatham's 'spigot' exact real calculator + * available, or any other method of generating 8336 fractional hex + * digits of pi on standard output, you can regenerate these tables + * exactly as below using the following Perl script (adjusting the + * first line or two if your pi-generator is not spigot). + +open my $spig, "spigot -n -B16 -d8336 pi |"; +read $spig, $ignore, 2; # throw away the leading "3." +for my $name ("parray", "sbox0".."sbox3") { + print "static const word32 ${name}[] = {\n"; + my $len = $name eq "parray" ? 18 : 256; + for my $i (1..$len) { + read $spig, $word, 8; + printf "%s0x%s,", ($i%6==1 ? " " : " "), uc $word; + print "\n" if ($i == $len || $i%6 == 0); + } + print "};\n\n"; +} +close $spig; + */ static const word32 parray[] = { 0x243F6A88, 0x85A308D3, 0x13198A2E, 0x03707344, 0xA4093822, 0x299F31D0, @@ -305,6 +327,24 @@ static void blowfish_lsb_encrypt_cbc(unsigned char *blk, int len, ctx->iv1 = iv1; } +void blowfish_lsb_encrypt_ecb(unsigned char *blk, int len, + BlowfishContext * ctx) +{ + word32 xL, xR, out[2]; + + assert((len & 7) == 0); + + while (len > 0) { + xL = GET_32BIT_LSB_FIRST(blk); + xR = GET_32BIT_LSB_FIRST(blk + 4); + blowfish_encrypt(xL, xR, out, ctx); + PUT_32BIT_LSB_FIRST(blk, out[0]); + PUT_32BIT_LSB_FIRST(blk + 4, out[1]); + blk += 8; + len -= 8; + } +} + static void blowfish_lsb_decrypt_cbc(unsigned char *blk, int len, BlowfishContext * ctx) { @@ -415,8 +455,25 @@ static void blowfish_msb_sdctr(unsigned char *blk, int len, ctx->iv1 = iv1; } -static void blowfish_setkey(BlowfishContext * ctx, - const unsigned char *key, short keybytes) +void blowfish_initkey(BlowfishContext *ctx) +{ + int i; + + for (i = 0; i < 18; i++) { + ctx->P[i] = parray[i]; + } + + for (i = 0; i < 256; i++) { + ctx->S0[i] = sbox0[i]; + ctx->S1[i] = sbox1[i]; + ctx->S2[i] = sbox2[i]; + ctx->S3[i] = sbox3[i]; + } +} + +void blowfish_expandkey(BlowfishContext * ctx, + const unsigned char *key, short keybytes, + const unsigned char *salt, short saltbytes) { word32 *S0 = ctx->S0; word32 *S1 = ctx->S1; @@ -424,10 +481,18 @@ static void blowfish_setkey(BlowfishContext * ctx, word32 *S3 = ctx->S3; word32 *P = ctx->P; word32 str[2]; - int i; + int i, j; + int saltpos; + unsigned char dummysalt[1]; + + saltpos = 0; + if (!salt) { + saltbytes = 1; + salt = dummysalt; + dummysalt[0] = 0; + } for (i = 0; i < 18; i++) { - P[i] = parray[i]; P[i] ^= ((word32) (unsigned char) (key[(i * 4 + 0) % keybytes])) << 24; P[i] ^= @@ -437,48 +502,59 @@ static void blowfish_setkey(BlowfishContext * ctx, P[i] ^= ((word32) (unsigned char) (key[(i * 4 + 3) % keybytes])); } - for (i = 0; i < 256; i++) { - S0[i] = sbox0[i]; - S1[i] = sbox1[i]; - S2[i] = sbox2[i]; - S3[i] = sbox3[i]; - } - str[0] = str[1] = 0; for (i = 0; i < 18; i += 2) { + for (j = 0; j < 8; j++) + str[j/4] ^= ((word32)salt[saltpos++ % saltbytes]) << (24-8*(j%4)); + blowfish_encrypt(str[0], str[1], str, ctx); P[i] = str[0]; P[i + 1] = str[1]; } for (i = 0; i < 256; i += 2) { + for (j = 0; j < 8; j++) + str[j/4] ^= ((word32)salt[saltpos++ % saltbytes]) << (24-8*(j%4)); blowfish_encrypt(str[0], str[1], str, ctx); S0[i] = str[0]; S0[i + 1] = str[1]; } for (i = 0; i < 256; i += 2) { + for (j = 0; j < 8; j++) + str[j/4] ^= ((word32)salt[saltpos++ % saltbytes]) << (24-8*(j%4)); blowfish_encrypt(str[0], str[1], str, ctx); S1[i] = str[0]; S1[i + 1] = str[1]; } for (i = 0; i < 256; i += 2) { + for (j = 0; j < 8; j++) + str[j/4] ^= ((word32)salt[saltpos++ % saltbytes]) << (24-8*(j%4)); blowfish_encrypt(str[0], str[1], str, ctx); S2[i] = str[0]; S2[i + 1] = str[1]; } for (i = 0; i < 256; i += 2) { + for (j = 0; j < 8; j++) + str[j/4] ^= ((word32)salt[saltpos++ % saltbytes]) << (24-8*(j%4)); blowfish_encrypt(str[0], str[1], str, ctx); S3[i] = str[0]; S3[i + 1] = str[1]; } } +static void blowfish_setkey(BlowfishContext *ctx, + const unsigned char *key, short keybytes) +{ + blowfish_initkey(ctx); + blowfish_expandkey(ctx, key, keybytes, NULL, 0); +} + /* -- Interface with PuTTY -- */ #define SSH_SESSION_KEY_LENGTH 32 -static void *blowfish_make_context(void) +void *blowfish_make_context(void) { return snew(BlowfishContext); } @@ -489,7 +565,7 @@ static void *blowfish_ssh1_make_context(void) return snewn(2, BlowfishContext); } -static void blowfish_free_context(void *handle) +void blowfish_free_context(void *handle) { sfree(handle); } @@ -565,16 +641,18 @@ const struct ssh_cipher ssh_blowfish_ssh1 = { static const struct ssh2_cipher ssh_blowfish_ssh2 = { blowfish_make_context, blowfish_free_context, blowfish_iv, blowfish_key, - blowfish_ssh2_encrypt_blk, blowfish_ssh2_decrypt_blk, + blowfish_ssh2_encrypt_blk, blowfish_ssh2_decrypt_blk, NULL, NULL, "blowfish-cbc", - 8, 128, SSH_CIPHER_IS_CBC, "Blowfish-128 CBC" + 8, 128, 16, SSH_CIPHER_IS_CBC, "Blowfish-128 CBC", + NULL }; static const struct ssh2_cipher ssh_blowfish_ssh2_ctr = { blowfish_make_context, blowfish_free_context, blowfish_iv, blowfish256_key, - blowfish_ssh2_sdctr, blowfish_ssh2_sdctr, + blowfish_ssh2_sdctr, blowfish_ssh2_sdctr, NULL, NULL, "blowfish-ctr", - 8, 256, 0, "Blowfish-256 SDCTR" + 8, 256, 32, 0, "Blowfish-256 SDCTR", + NULL }; static const struct ssh2_cipher *const blowfish_list[] = {