Esempio n. 1
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    def traverse(self, s):
        """Returns the auth nodes for leaf s + 1."""
        for h in range(H):
            if not ((s >> h) & 1):
                tau = h
                break
        if tau > 0:
            tempkeep = self.keep[(tau - 1) >> 1]  # prevent overwriting

        if not ((s >> (tau+1)) & 1) and tau < H - 1:
            self.keep[tau >> 1] = self.auth[tau]

        if tau == 0:
            self.auth[0] = Node(h=0, v=leafcalc(s))

        else:
            self.auth[tau] = Node(h=0, v=g(self.auth[tau - 1].v + tempkeep.v))
            for h in range(tau):
                if h < H - K:
                    self.auth[h] = self.treehash[h].node
                else:
                    offset = (1 << (H - 1 - h)) + h - H
                    rowidx = ((s >> h) - 1) >> 1
                    self.auth[h] = self.retain[offset + rowidx]
            for h in range(tau if (tau < H - K) else H - K):
                startidx = s + 1 + 3 * (1 << h)
                if startidx < 1 << H:
                    self.treehash[h].restart(startidx)
        return self.auth
    def traverse(self, s):
        """Returns the auth nodes for leaf s + 1."""
        for h in range(H):
            if not ((s >> h) & 1):
                tau = h
                break
        if tau > 0:
            tempkeep = self.keep[(tau - 1) >> 1]  # prevent overwriting

        if not ((s >> (tau + 1)) & 1) and tau < H - 1:
            self.keep[tau >> 1] = self.auth[tau]

        if tau == 0:
            self.auth[0] = Node(h=0, v=leafcalc(s))

        else:
            self.auth[tau] = Node(h=0, v=g(self.auth[tau - 1].v + tempkeep.v))
            for h in range(tau):
                if h < H - K:
                    self.auth[h] = self.treehash[h].node
                else:
                    offset = (1 << (H - 1 - h)) + h - H
                    rowidx = ((s >> h) - 1) >> 1
                    self.auth[h] = self.retain[offset + rowidx]
            for h in range(tau if (tau < H - K) else H - K):
                startidx = s + 1 + 3 * (1 << h)
                if startidx < 1 << H:
                    self.treehash[h].restart(startidx)
        return self.auth
 def update(self):
     """Performs one unit of computation on the stack. This can imply either
     the introduction a new leaf node or the computation of a parent node"""
     if self.completed:
         return
     if len(self.stack) >= 2 and self.stack[-1].h == self.stack[-2].h:
         node_r = self.stack.pop()
         node_l = self.stack.pop()
         self.stack.append(Node(h=node_l.h + 1, v=g(node_l.v + node_r.v)))
     else:
         self.stack.append(Node(h=0, v=leafcalc(self.next_idx)))
         self.next_idx += 1
     if self.stack[-1].h == self.h:
         self.completed = True
     return
Esempio n. 4
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 def update(self):
     """Performs one unit of computation on the stack. This can imply either
     the introduction a new leaf node or the computation of a parent node"""
     if self.completed:
         return
     if len(self.stack) >= 2 and self.stack[-1].h == self.stack[-2].h:
         node_r = self.stack.pop()
         node_l = self.stack.pop()
         self.stack.append(Node(h=node_l.h + 1, v=g(node_l.v + node_r.v)))
     else:
         self.stack.append(Node(h=0, v=leafcalc(self.next_idx)))
         self.next_idx += 1
     if self.stack[-1].h == self.h:
         self.completed = True
     return
 def update(self):
     """Performs one iteration of Treehash, i.e. adds one leaf node.
     Note that this is different from Treehash.update() in the classic
     traversal algorithm, where only one computational unit is performed."""
     node1 = Node(h=0, v=leafcalc(self.next_idx))
     while self.stackusage > 0 and STACK[-1].h == node1.h:
         node2 = STACK.pop()
         self.stackusage -= 1
         node1 = Node(h=node1.h + 1, v=g(node2.v + node1.v))
     STACK.append(node1)
     self.stackusage += 1
     self.next_idx += 1
     if self.stackusage == 1 and STACK[-1].h == self.h:
         self.completed = True
         self.node = STACK.pop()
         self.stackusage -= 1
 def update(self):
     """Performs one iteration of Treehash, i.e. adds one leaf node.
     Note that this is different from Treehash.update() in the classic
     traversal algorithm, where only one computational unit is performed."""
     node1 = Node(h=0, v=leafcalc(self.next_idx))
     while self.stackusage > 0 and self.stack[-1].h == node1.h:
         node2 = self.stack.pop()
         self.stackusage -= 1
         node1 = Node(h=node1.h + 1, v=g(node2.v + node1.v))
     self.stack.append(node1)
     self.stackusage += 1
     self.next_idx += 1
     if self.stackusage == 1 and self.stack[-1].h == self.h:
         self.completed = True
         self.node = self.stack.pop()
         self.stackusage -= 1
Esempio n. 7
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def traverse(s):
    """Returns the auth nodes for leaf s + 1."""
    for h in range(H):
        if not ((s >> h) & 1):
            tau = h
            break

    if tau > 0:
        tempKEEP = KEEP[(tau - 1) >> 1]  # prevent overwriting too soon

    if not ((s >> (tau + 1)) & 1) and tau < H - 1:
        KEEP[tau >> 1] = AUTH[tau]

    if tau == 0:
        AUTH[0] = Node(h=0, v=leafcalc(s))

    else:
        AUTH[tau] = Node(h=0, v=g(AUTH[tau - 1].v + tempKEEP.v))
        for h in range(tau):
            if h < H - K:
                AUTH[h] = TREEHASH[h].node
            else:
                offset = (1 << (H - 1 - h)) + h - H
                rowidx = ((s >> h) - 1) >> 1
                AUTH[h] = RETAIN[offset + rowidx]
        for h in range(tau if (tau < H - K) else H - K):
            startidx = s + 1 + 3 * (1 << h)
            if startidx < 1 << H:
                TREEHASH[h].__init__(h, startidx)

    for _ in range((H - K) >> 1):
        l_min = H
        h = H - K
        for j in range(H - K):
            if TREEHASH[j].completed:
                low = H
            elif TREEHASH[j].stackusage == 0:
                low = j
            else:
                low = TREEHASH[j].height()
            if low < l_min:
                h = j
                l_min = low
        if h != H - K:
            TREEHASH[h].update()

    return AUTH
 def stack_update(self, idx):
     node1 = Node(h=0, v=leafcalc(idx))
     if node1.h < H - K and idx == 3:
         self.treehash[0].node = node1
     while self.stack and self.stack[-1].h == node1.h:
         if idx >> node1.h == 1:
             self.auth[node1.h] = node1
         else:  # node1 is a right-node with row-index 2idx + 3
             if node1.h < H - K and idx >> node1.h == 3:
                 self.treehash[node1.h].node = node1
             elif node1.h >= H - K:
                 offset = (1 << (H - 1 - node1.h)) + node1.h - H
                 rowidx = ((idx >> node1.h) - 3) >> 1
                 self.retain[offset + rowidx] = node1
         node2 = self.stack.pop()
         node1 = Node(h=node1.h + 1, v=g(node2.v + node1.v))
     self.stack.append(node1)
Esempio n. 9
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 def stack_update(self, idx):
     node1 = Node(h=0, v=leafcalc(idx))
     if node1.h < H - K and idx == 3:
         self.treehash[0].node = node1
     while self.stack and self.stack[-1].h == node1.h:
         if idx >> node1.h == 1:
             self.auth[node1.h] = node1
         else:  # node1 is a right-node with row-index 2idx + 3
             if node1.h < H - K and idx >> node1.h == 3:
                 self.treehash[node1.h].node = node1
             elif node1.h >= H - K:
                 offset = (1 << (H - 1 - node1.h)) + node1.h - H
                 rowidx = ((idx >> node1.h) - 3) >> 1
                 self.retain[offset + rowidx] = node1
         node2 = self.stack.pop()
         node1 = Node(h=node1.h + 1, v=g(node2.v + node1.v))
     self.stack.append(node1)
def keygen_and_setup():
    """Sets up TREEHASH and AUTH for the start of classic Merkle traversal."""
    for h in range(H):
        TREEHASH[h] = Treehash(h, completed=True)
    stack = []
    for j in range(2 ** H):
        node1 = Node(h=0, v=leafcalc(j))
        if j == 0:
            TREEHASH[0].stack = [node1]
        while stack and stack[-1].h == node1.h:
            if not AUTH[node1.h]:
                AUTH[node1.h] = node1
            node2 = stack.pop()
            node1 = Node(h=node1.h+1, v=g(node2.v + node1.v))
            if node1.h < H and not TREEHASH[node1.h].stack:
                TREEHASH[node1.h].stack.append(node1)
        stack.append(node1)
    return stack.pop()
Esempio n. 11
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def keygen_and_setup():
    """Sets up TREEHASH and AUTH for the start of classic Merkle traversal."""
    for h in range(H):
        TREEHASH[h] = Treehash(h, completed=True)
    stack = []
    for j in range(2**H):
        node1 = Node(h=0, v=leafcalc(j))
        if j == 0:
            TREEHASH[0].stack = [node1]
        while stack and stack[-1].h == node1.h:
            if not AUTH[node1.h]:
                AUTH[node1.h] = node1
            node2 = stack.pop()
            node1 = Node(h=node1.h + 1, v=g(node2.v + node1.v))
            if node1.h < H and not TREEHASH[node1.h].stack:
                TREEHASH[node1.h].stack.append(node1)
        stack.append(node1)
    return stack.pop()
def traverse(s):
    """Returns the auth nodes for leaf s + 1."""
    tau = next(h for h in range(H) if not (s >> h) & 1)

    if not (s >> (tau + 1)) & 1 and tau < H - 1:
        KEEP[tau] = AUTH[tau]

    if tau == 0:
        AUTH[0] = Node(h=0, v=leafcalc(s))

    else:
        AUTH[tau] = Node(h=tau, v=g(AUTH[tau - 1].v + KEEP[tau - 1].v))
        KEEP[tau - 1] = None
        for h in range(tau):
            if h < H - K:
                AUTH[h] = TREEHASH[h].node
                TREEHASH[h].node = None
            else:
                AUTH[h] = RETAIN[h].pop()
        for h in range(min(tau, H - K)):
            startidx = s + 1 + 3 * 2**h
            if startidx < 2**H:
                TREEHASH[h].__init__(h, startidx)

    for _ in range((H - K) // 2):
        l_min = float('inf')
        h = None
        for j in range(H - K):
            if TREEHASH[j].completed:
                low = float('inf')
            elif TREEHASH[j].stackusage == 0:
                low = j
            else:
                low = TREEHASH[j].height()
            if low < l_min:
                h = j
                l_min = low
        if h is not None:
            TREEHASH[h].update()

    return AUTH
def traverse(s):
    """Returns the auth nodes for leaf s + 1."""
    tau = next(h for h in range(H) if not (s >> h) & 1)

    if not (s >> (tau+1)) & 1 and tau < H - 1:
        KEEP[tau] = AUTH[tau]

    if tau == 0:
        AUTH[0] = Node(h=0, v=leafcalc(s))

    else:
        AUTH[tau] = Node(h=tau, v=g(AUTH[tau - 1].v + KEEP[tau - 1].v))
        KEEP[tau - 1] = None
        for h in range(tau):
            if h < H - K:
                AUTH[h] = TREEHASH[h].node
                TREEHASH[h].node = None
            else:
                AUTH[h] = RETAIN[h].pop()
        for h in range(min(tau, H - K)):
            startidx = s + 1 + 3 * 2**h
            if startidx < 2 ** H:
                TREEHASH[h].__init__(h, startidx)

    for _ in range((H - K) // 2):
        l_min = float('inf')
        h = None
        for j in range(H - K):
            if TREEHASH[j].completed:
                low = float('inf')
            elif TREEHASH[j].stackusage == 0:
                low = j
            else:
                low = TREEHASH[j].height()
            if low < l_min:
                h = j
                l_min = low
        if h is not None:
            TREEHASH[h].update()

    return AUTH
def keygen_and_setup():
    """Sets up TREEHASH, RETAIN and AUTH for the start of BDS traversal."""
    for h in range(H - K):
        TREEHASH[h] = Treehash(h, completed=True)
    stack = []
    for j in range(2**H):
        node1 = Node(h=0, v=leafcalc(j))
        if node1.h < H - K and j == 3:
            TREEHASH[0].node = node1
        while stack and stack[-1].h == node1.h:
            if not AUTH[node1.h]:
                AUTH[node1.h] = node1
            else:  # in this case node1 is a right-node with row-index 2j + 3
                if node1.h < H - K and TREEHASH[node1.h].node is None:
                    TREEHASH[node1.h].node = node1
                elif node1.h >= H - K:
                    RETAIN[node1.h].appendleft(node1)
            node2 = stack.pop()
            node1 = Node(h=node1.h + 1, v=g(node2.v + node1.v))
        stack.append(node1)
    return stack.pop()
def keygen_and_setup():
    """Sets up TREEHASH, RETAIN and AUTH for the start of BDS traversal."""
    for h in range(H - K):
        TREEHASH[h] = Treehash(h, completed=True)
    stack = []
    for j in range(2 ** H):
        node1 = Node(h=0, v=leafcalc(j))
        if node1.h < H - K and j == 3:
            TREEHASH[0].node = node1
        while stack and stack[-1].h == node1.h:
            if not AUTH[node1.h]:
                AUTH[node1.h] = node1
            else:  # in this case node1 is a right-node with row-index 2j + 3
                if node1.h < H - K and TREEHASH[node1.h].node is None:
                    TREEHASH[node1.h].node = node1
                elif node1.h >= H - K:
                    RETAIN[node1.h].appendleft(node1)
            node2 = stack.pop()
            node1 = Node(h=node1.h + 1, v=g(node2.v + node1.v))
        stack.append(node1)
    return stack.pop()
Esempio n. 16
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def keygen_and_setup():
    """Sets up TREEHASH, RETAIN and AUTH for the start of BDS traversal."""
    for h in range(H - K):
        TREEHASH[h] = Treehash(h, completed=True)
    stack = []
    for j in range(1 << H):
        node1 = Node(h=0, v=leafcalc(j))
        if node1.h < H - K and j == 3:
            TREEHASH[0].node = node1
        while stack and stack[-1].h == node1.h:
            if j >> node1.h == 1:
                AUTH[node1.h] = node1
            else:  # in this case node1 is a right-node with row-index 2j + 3
                if node1.h < H - K and j >> node1.h == 3:
                    TREEHASH[node1.h].node = node1
                elif node1.h >= H - K:
                    offset = (1 << (H - 1 - node1.h)) + node1.h - H
                    rowidx = ((j >> node1.h) - 3) >> 1
                    RETAIN[offset + rowidx] = node1
            node2 = stack.pop()
            node1 = Node(h=node1.h + 1, v=g(node2.v + node1.v))
        stack.append(node1)
    return stack.pop()