Correct std feature-flagging

If a crate has std set, it should enable std for all dependencies in order to
let them properly select which algorithms to use. Some crates fallback to
slower/worse algorithms on no-std.

Also more aggressively sets default-features = false leading to a *10%*
reduction in the amount of crates coordinator builds.

crypto/ciphersuite/Cargo.toml

@@ -38,15 +38,36 @@ k256 = { version = "^0.13.1", default-features = false, features = ["arithmetic"
 minimal-ed448 = { path = "../ed448", version = "0.4", default-features = false, optional = true }
 
 [dev-dependencies]
-hex = "0.4"
+hex = { version = "0.4", default-features = false, features = ["std"] }
 
-rand_core = { version = "0.6", features = ["std"] }
+rand_core = { version = "0.6", default-features = false, features = ["std"] }
 
 ff-group-tests = { version = "0.13", path = "../ff-group-tests" }
 
 [features]
 alloc = ["std-shims"]
-std = ["zeroize/std", "std-shims/std"]
+std = [
+  "std-shims/std",
+
+  "rand_core/std",
+
+  "zeroize/std",
+  "subtle/std",
+
+  "digest/std",
+  "transcript/std",
+  "sha2?/std",
+  "sha3?/std",
+
+  "ff/std",
+
+  "dalek-ff-group?/std",
+
+  "elliptic-curve?/std",
+  "p256?/std",
+  "k256?/std",
+  "minimal-ed448?/std",
+]
 
 dalek = ["sha2", "dalek-ff-group"]
 ed25519 = ["dalek"]

crypto/dalek-ff-group/Cargo.toml

@@ -32,5 +32,9 @@ sha2 = { version = "0.10", default-features = false }
 curve25519-dalek = { version = ">= 4.0, < 4.2", default-features = false, features = ["alloc", "zeroize", "digest", "group", "precomputed-tables"] }
 
 [dev-dependencies]
-rand_core = { version = "0.6", features = ["std"] }
+rand_core = { version = "0.6", default-features = false, features = ["std"] }
 ff-group-tests = { path = "../ff-group-tests" }
+
+[features]
+std = ["zeroize/std", "subtle/std", "rand_core/std", "digest/std", "sha2/std"]
+default = ["std"]

crypto/dkg/Cargo.toml

@@ -40,16 +40,22 @@ ciphersuite = { path = "../ciphersuite", default-features = false, features = ["
 [features]
 std = [
   "thiserror",
+
   "rand_core/std",
 
   "std-shims/std",
 
-  "ciphersuite/std",
+  "serde/std",
 
-  "multiexp/batch",
+  "transcript/std",
+  "chacha20/std",
+
+  "ciphersuite/std",
   "multiexp/std",
+  "multiexp/batch",
 
   "schnorr/std",
+  "dleq/std",
   "dleq/serialize"
 ]
 serde = ["dep:serde"]

crypto/dleq/Cargo.toml

@@ -41,15 +41,18 @@ dalek-ff-group = { path = "../dalek-ff-group" }
 transcript = { package = "flexible-transcript", path = "../transcript", features = ["recommended"] }
 
 [features]
-std = []
+std = ["rand_core/std", "zeroize/std", "digest/std", "transcript/std", "ff/std", "multiexp?/std"]
 serialize = ["std"]
 
 # Needed for cross-group DLEqs
 secure_capacity_difference = []
 experimental = ["std", "thiserror", "multiexp"]
 
-# Only applies to experimental, yet is default to ensure security
-# experimental doesn't mandate it itself in case two curves with extreme
-# capacity differences are desired to be used together, in which case the user
-# must specify experimental without default features
-default = ["secure_capacity_difference"]
+default = [
+  "std",
+  # Only applies to experimental, yet is default to ensure security
+  # experimental doesn't mandate it itself in case two curves with extreme
+  # capacity differences are desired to be used together, in which case the user
+  # must specify experimental without default features
+  "secure_capacity_difference"
+]

crypto/ed448/Cargo.toml

@@ -28,8 +28,12 @@ generic-array = { version = "1", default-features = false }
 crypto-bigint = { version = "0.5", default-features = false, features = ["zeroize"] }
 
 [dev-dependencies]
-hex = "0.4"
+hex = { version = "0.4", default-features = false, features = ["std"] }
 
-rand_core = { version = "0.6", features = ["std"] }
+rand_core = { version = "0.6", default-features = false, features = ["std"] }
 
 ff-group-tests = { path = "../ff-group-tests" }
+
+[features]
+std = ["rand_core/std", "zeroize/std", "subtle/std", "ff/std"]
+default = ["std"]

crypto/multiexp/Cargo.toml

@@ -32,7 +32,7 @@ k256 = { version = "^0.13.1", default-features = false, features = ["arithmetic"
 dalek-ff-group = { path = "../dalek-ff-group" }
 
 [features]
-std = ["std-shims/std", "zeroize/std"]
+std = ["std-shims/std", "zeroize/std", "ff/std", "rand_core/std"]
 
 batch = ["rand_core"]
 

crypto/schnorr/Cargo.toml

@@ -36,5 +36,5 @@ dalek-ff-group = { path =  "../dalek-ff-group" }
 ciphersuite = { path = "../ciphersuite", features = ["ed25519"] }
 
 [features]
-std = ["std-shims/std", "ciphersuite/std", "multiexp/std"]
+std = ["std-shims/std", "rand_core/std", "zeroize/std", "transcript/std", "ciphersuite/std", "multiexp/std"]
 default = ["std"]

crypto/transcript/Cargo.toml

@@ -29,6 +29,8 @@ sha2 = { version = "0.10", default-features = false }
 blake2 = { version = "0.10", default-features = false }
 
 [features]
+std = ["subtle/std", "zeroize/std", "digest/std", "blake2?/std", "merlin?/std"]
 recommended = ["blake2"]
 merlin = ["dep:merlin"]
 tests = []
+default = ["std"]