Sesstion token generation + storage

1 files changed, 42 insertions, 0 deletions

diff --git a/backend/src/Authentication/Tokens.zig b/backend/src/Authentication/Tokens.zig
new file mode 100644
index 0000000..6548ce7
--- /dev/null
+++ b/backend/src/Authentication/Tokens.zig
@@ -0,0 +1,42 @@
+const std = @import("std");
+const redis = @import("../Redis/Connection.zig");
+const userModel = @import("../Models/User.zig");
+
+const topicName = "cp2020_auth";
+const token_ttl: u16 = 43_200; // 12 hours
+
+var prng: std.Random.DefaultPrng= undefined;
+var rnd: std.Random = undefined;
+
+pub fn Init() !void {
+    // Random enough
+    var seed: u64 = undefined;
+    try std.posix.getrandom(std.mem.asBytes(&seed));
+    prng = std.Random.DefaultPrng.init(seed);
+    rnd = prng.random();
+}
+
+/// Generates a new token in the heap. Expects [64]u8 as an input 
+fn generateSessionToken(buf: []u8) []u8 {
+    for (0..64) |i| {
+        buf[i] = std.Random.intRangeAtMost(rnd, u8, 'A', 'z');
+    }
+    return buf;
+}
+
+pub fn GenerateNewSession(allocator: std.mem.Allocator, user: userModel.User) ![]u8 {
+    const token: []u8 = try allocator.alloc(u8, 64);
+    const newToken = generateSessionToken(token);
+
+    // Redis cache 
+    var string: std.io.Writer.Allocating = .init(allocator);
+    defer string.deinit();
+    try string.writer.print("{f}", .{std.json.fmt(user, .{})});
+    try redis.WriteToTopic(topicName, redis.Message {
+        .Key = token,
+        .Value = string.written(),
+        .SecondsToLive = token_ttl,
+    });
+
+    return newToken;
+}