From d4360a4f8b7d29aedf6f9af0a878a9060d434ea2 Mon Sep 17 00:00:00 2001
From: Markus Teich <markus.teich@stusta.mhn.de>
Date: Wed, 8 Jun 2016 15:40:22 +0200
Subject: [PATCH] fix typos and types

---
 gp-scripts/m+1stPrice | 91 +++++++++++++++++++++++++++++++++++++++++++
 smc.c                 | 14 ++++---
 2 files changed, 99 insertions(+), 6 deletions(-)
 create mode 100644 gp-scripts/m+1stPrice

diff --git a/gp-scripts/m+1stPrice b/gp-scripts/m+1stPrice
new file mode 100644
index 0000000..8407e96
--- /dev/null
+++ b/gp-scripts/m+1stPrice
@@ -0,0 +1,91 @@
+\\ From: "Fully private auctions in a constant number of rounds" (2003) by Felix Brandt pages 9-10
+
+
+\\\\\\\\\\\\
+\\ Adapt the following values to your needs
+\\\\\\\\\\\\
+
+\\ amount of bidders
+n = 2^3
+\\ amount of possible prices
+k = 2^7
+\\ randomize bids (change to something static, if you like)
+bid = vector(n,i,random(k)+1)
+\\bid = vector(n,i,n-i+1)     \\ first bidder wins
+\\bid = vector(n,i,i)         \\ last bidder wins
+\\bid = vector(n,i,(i+1)%2)   \\ second bidder wins (with ties)
+
+\\ prime finite field setup (result may be ambiguous if your prime is too small, 4*n*k seems to work fine)
+q = prime(4*n*k)
+
+\\\\\\\\\\\\
+\\ SETUP
+\\\\\\\\\\\\
+
+\\ p not needed? wat?
+\\p = 47
+
+\\ get generator / primitive element for Z_q
+var = 'x                                                    \\ copy pasta from internet
+pe=ffgen(minpoly(ffprimroot(ffgen(ffinit(q,1))),var),var)   \\ get primitive element
+1/(fforder(pe) == q-1)                                      \\ error out, if ord(pe) is wrong
+g = Mod(eval(Str(pe)), q)                                   \\ dirty hack to convert t_FFELEM to t_INT
+
+\\\\\\\\\\\\
+\\ PROLOG
+\\\\\\\\\\\\
+
+\\ private keys of agents
+x = vector(n,i,random(q))
+\\ public keyshares of agents
+yshares = vector(n,i,g^x[i])
+\\ shared public key
+y = prod(X=1,n,yshares[X])
+
+\\ first index level = owning agent id (additive share)
+\\ second index level = agent id, price id
+m = vector(n,i,matrix(n,k,a,b,random(q)))
+
+\\ index = owning agent id, price id
+r = matrix(n,k,i,j,random(q))
+\\ bid matrix
+b = matrix(n,k,i,j,g^(bid[i]==j))
+
+\\\\\\\\\\\\
+\\ ROUND1
+\\\\\\\\\\\\
+
+\\ encrypted bids
+alpha = matrix(n,k,i,j, b[i,j]*y^r[i,j])
+beta  = matrix(n,k,i,j,        g^r[i,j])
+
+\\\\\\\\\\\\
+\\ ROUND2
+\\\\\\\\\\\\
+
+\\ multiplicative shares
+\\ first index level = owning agent id (multiplicative share)
+\\ second index level = agent id, price id
+Gamma = vector(n,a,matrix(n,k,i,j, ( prod(h=1,n,prod(d=j+1,k,alpha[h,d])) * prod(d=1,j-1,alpha[i,d]) * prod(h=1,i-1,alpha[h,j]) )^m[a][i,j] ))
+Delta = vector(n,a,matrix(n,k,i,j, ( prod(h=1,n,prod(d=j+1,k, beta[h,d])) * prod(d=1,j-1, beta[i,d]) * prod(h=1,i-1, beta[h,j]) )^m[a][i,j] ))
+
+\\\\\\\\\\\\
+\\ ROUND3
+\\\\\\\\\\\\
+
+\\ multiplicative shares (decryption)
+\\ first index level = owning agent id (multiplicative share)
+\\ second index level = agent id, price id
+Phi = vector(n,a,matrix(n,k,i,j, prod(h=1,n,Delta[h][i,j])^x[a] ))
+
+\\\\\\\\\\\\
+\\ EPILOG
+\\\\\\\\\\\\
+
+\\ winner matrix
+v = matrix(n,k,a,j, prod(i=1,n,Gamma[i][a,j]) / prod(i=1,n,Phi[i][a,j]) )
+
+vi = lift(v)
+
+print("bids are: ", bid)
+for(X=1,n, if(vecmin(vi[X,])==1, print("And the winner is ", X) ))
diff --git a/smc.c b/smc.c
index 02dfafc..399f031 100644
--- a/smc.c
+++ b/smc.c
@@ -24,7 +24,7 @@
 #include <pari/pari.h>
 
 GEN
-smc_hextodec (char *s)                      /* int */
+smc_hextodec (const char *s)                      /* int */
 {
 	size_t i;
 	char c;
@@ -46,7 +46,7 @@ smc_hextodec (char *s)                      /* int */
 
 
 void
-smc_genbid (AuctionData *ad, uint16_t bid)
+smc_genbid (struct AuctionData *ad, uint16_t bid)
 {
 	uint16_t j;
 	pari_sp ltop = avma;
@@ -59,8 +59,9 @@ smc_genbid (AuctionData *ad, uint16_t bid)
 	ad->b = gerepilecopy (ltop, ret);
 }
 
+
 void
-smc_genalpha (AuctionData *ad)
+smc_genalpha (struct AuctionData *ad)
 {
 	uint16_t j;
 	pari_sp ltop = avma;
@@ -70,11 +71,12 @@ smc_genalpha (AuctionData *ad)
 	{
 		gel (ret, j) = gmul (gel (ad->b, j), gpowgi (ad->y, gel (ad->r, j)));
 	}
-	ab->alpha = gerepilecopy (ltop, ret);
+	ad->alpha = gerepilecopy (ltop, ret);
 }
 
+
 void
-smc_genbeta (AuctionData *ad)
+smc_genbeta (struct AuctionData *ad)
 {
 	uint16_t j;
 	pari_sp ltop = avma;
@@ -84,6 +86,6 @@ smc_genbeta (AuctionData *ad)
 	{
 		gel (ret, j) = gpowgi (ad->g, gel (ad->r, j));
 	}
-	ab->beta = gerepilecopy (ltop, ret);
+	ad->beta = gerepilecopy (ltop, ret);
 }