Remove the client SRP6 class, really free standing functions are fine

for this.

Add a new function that identifies a named SRP group from the N/g
params - this is important as we need to verify the SRP groups, the
easiest way to do that is to to force them to be a known/published
value.

Add the 1536, 3072, 4096, 6144, and 8192 bit groups from RFC 5054

3 files changed, 152 insertions, 47 deletions

diff --git a/src/constructs/srp6/srp6.cpp b/src/constructs/srp6/srp6.cpp
index 287f0bdfb..cb9bf27bc 100644
--- a/src/constructs/srp6/srp6.cpp
+++ b/src/constructs/srp6/srp6.cpp
@@ -69,14 +69,37 @@ BigInt compute_x(const std::string& hash_id,
 
 }
 
+std::string srp6_group_identifier(const BigInt& N, const BigInt& g)
+   {
+   /*
+   This function assumes that only one 'standard' SRP parameter set has
+   been defined for a particular bitsize. As of this writing that is the case.
+   */
+   try
+      {
+      const std::string group_name = "modp/srp/" + to_string(N.bits());
+
+      DL_Group group(group_name);
+
+      if(group.get_p() == N && group.get_g() == g)
+         return group_name;
+
+      throw std::runtime_error("Unknown SRP params");
+      }
+   catch(...)
+      {
+      throw Invalid_Argument("Bad SRP group parameters");
+      }
+   }
+
 std::pair<BigInt, SymmetricKey>
-SRP6_Client_Session:: step1(const std::string& identifier,
-                            const std::string& password,
-                            const std::string& group_id,
-                            const std::string& hash_id,
-                            const MemoryRegion<byte>& salt,
-                            const BigInt& B,
-                            RandomNumberGenerator& rng)
+srp6_client_agree(const std::string& identifier,
+                  const std::string& password,
+                  const std::string& group_id,
+                  const std::string& hash_id,
+                  const MemoryRegion<byte>& salt,
+                  const BigInt& B,
+                  RandomNumberGenerator& rng)
    {
    DL_Group group(group_id);
    const BigInt& g = group.get_g();
@@ -104,11 +127,11 @@ SRP6_Client_Session:: step1(const std::string& identifier,
    return std::make_pair(A, Sk);
    }
 
-BigInt SRP6_Client_Session::generate_verifier(const std::string& identifier,
-                                              const std::string& password,
-                                              const MemoryRegion<byte>& salt,
-                                              const std::string& group_id,
-                                              const std::string& hash_id)
+BigInt generate_srp6_verifier(const std::string& identifier,
+                              const std::string& password,
+                              const MemoryRegion<byte>& salt,
+                              const std::string& group_id,
+                              const std::string& hash_id)
    {
    const BigInt x = compute_x(hash_id, identifier, password, salt);
 
diff --git a/src/constructs/srp6/srp6.h b/src/constructs/srp6/srp6.h
index 01bd2a4c7..bf5cb4863 100644
--- a/src/constructs/srp6/srp6.h
+++ b/src/constructs/srp6/srp6.h
@@ -17,44 +17,42 @@
 namespace Botan {
 
 /**
-* Represents a SRP-6a client session
+* SRP6a Client side
+* @param username the username we are attempting login for
+* @param password the password we are attempting to use
+* @param group_id specifies the shared SRP group
+* @param hash_id specifies a secure hash function
+* @param salt is the salt value sent by the server
+* @param B is the server's public value
+* @param rng is a random number generator
+*
+* @return (A,K) the client public key and the shared secret key
 */
-class BOTAN_DLL SRP6_Client_Session
-   {
-   public:
+std::pair<BigInt,SymmetricKey> srp6_client_agree(const std::string& username,
+                                                 const std::string& password,
+                                                 const std::string& group_id,
+                                                 const std::string& hash_id,
+                                                 const MemoryRegion<byte>& salt,
+                                                 const BigInt& B,
+                                                 RandomNumberGenerator& rng);
 
-      /**
-      * Client side step 1
-      * @param username the username we are attempting login for
-      * @param password the password we are attempting to use
-      * @param group_id specifies the shared SRP group
-      * @param hash_id specifies a secure hash function
-      * @param salt is the salt value sent by the server
-      * @param B is the server's public value
-      * @param rng is a random number generator
-      *
-      * @return (A,K) the client public key and the shared secret key
-      */
-      std::pair<BigInt,SymmetricKey> step1(const std::string& username,
-                                           const std::string& password,
-                                           const std::string& group_id,
-                                           const std::string& hash_id,
-                                           const MemoryRegion<byte>& salt,
-                                           const BigInt& B,
-                                           RandomNumberGenerator& rng);
+/**
+* Generate a new SRP-6 verifier
+* @param identifier a username or other client identifier
+* @param password the secret used to authenticate user
+* @param salt a randomly chosen value, at least 128 bits long
+*/
+BigInt generate_srp6_verifier(const std::string& identifier,
+                              const std::string& password,
+                              const MemoryRegion<byte>& salt,
+                              const std::string& group_id,
+                              const std::string& hash_id);
 
-      /**
-      * Generate a new SRP-6 verifier
-      * @param identifier a username or other client identifier
-      * @param password the secret used to authenticate user
-      * @param salt a randomly chosen value, at least 128 bits long
-      */
-      static BigInt generate_verifier(const std::string& identifier,
-                                      const std::string& password,
-                                      const MemoryRegion<byte>& salt,
-                                      const std::string& group_id,
-                                      const std::string& hash_id);
-   };
+/**
+* Return the group id for this SRP param set, or else thrown an
+* exception
+*/
+std::string srp6_group_identifier(const BigInt& N, const BigInt& g);
 
 /**
 * Represents a SRP-6a server session
diff --git a/src/libstate/policy.cpp b/src/libstate/policy.cpp
index 7abea7d4d..b1da22ce8 100644
--- a/src/libstate/policy.cpp
+++ b/src/libstate/policy.cpp
@@ -337,6 +337,15 @@ void set_default_dl_groups(Library_State& config)
          "NgRlEbmT//////////8="
          "-----END X942 DH PARAMETERS-----");
 
+   config.set("dl", "modp/srp/1536",
+         "-----BEGIN DH PARAMETERS-----"
+         "MIHHAoHBAJ3vPK+5OSd6sfEqhheke7vbpR30maxMgL7uqWFLGcxNX09fVW4ny95R"
+         "xqlL5GB6KRVYkDug0PhDgLZVu5oi6NzfAop87Gfw0IE0sci5eYkUm2CeC+O6tj1H"
+         "VIOB28Wx/HZOP0tT3Z2hFYv9PiucjPVu3wGVOTSWJ9sv1T0kt8SGZXcuQ31sf4zk"
+         "QnNK98y3roN8Jkrjqb64f4ov6bi1KS5aAh//XpFHnoznoowkQsbzFRgPk0maI03P"
+         "duP+0TX5uwIBAg=="
+         "-----END DH PARAMETERS-----");
+
    config.set("dl", "modp/ietf/2048",
          "-----BEGIN X942 DH PARAMETERS-----"
          "MIICDAKCAQEA///////////JD9qiIWjCNMTGYouA3BzRKQJOCIpnzHQCC76mOxOb"
@@ -388,6 +397,19 @@ void set_default_dl_groups(Library_State& config)
          "JcFokFSdaWV//////////w=="
          "-----END X942 DH PARAMETERS-----");
 
+   config.set("dl", "modp/srp/3072",
+         "-----BEGIN DH PARAMETERS-----"
+         "MIIBiAKCAYEA///////////JD9qiIWjCNMTGYouA3BzRKQJOCIpnzHQCC76mOxOb"
+         "IlFKCHmONATd75UZs806QxswKwpt8l8UN0/hNW1tUcJF5IW1dmJefsb0TELppjft"
+         "awv/XLb0Brft7jhr+1qJn6WunyQRfEsf5kkoZlHs5Fs9wgB8uKFjvwWY2kg2HFXT"
+         "mmkWP6j9JM9fg2VdI9yjrZYcYvNWIIVSu57VKQdwlpZtZww1Tkq8mATxdGwIyhgh"
+         "fDKQXkYuNs474553LBgOhgObJ4Oi7Aeij7XFXfBvTFLJ3ivL9pVYFxg5lUl86pVq"
+         "5RXSJhiY+gUQFXKOWoqqxC2tMxcNBFB6M6hVIavfHLpk7PuFBFjb7wqK6nFXXQYM"
+         "fbOXD4Wm4eTHq/WujNsJM9cejJTgSiVhnc7j0iYa0u5r8S/6BtmKCGTYdgJzPshq"
+         "ZFIfKxgXeyAMu+EXV3phXWx3CYjAutlG4gjiT6B05asxQ9tb/OD9EI5LgtEgqTrS"
+         "yv//////////AgEF"
+         "-----END DH PARAMETERS-----");
+
    config.set("dl", "modp/ietf/4096",
          "-----BEGIN X942 DH PARAMETERS-----"
          "MIIEDAKCAgEA///////////JD9qiIWjCNMTGYouA3BzRKQJOCIpnzHQCC76mOxOb"
@@ -414,6 +436,21 @@ void set_default_dl_groups(Library_State& config)
          "ydp1TEbH7uDDf9vuSFNgR6b6GuSaAxjM//////////8="
          "-----END X942 DH PARAMETERS-----");
 
+   config.set("dl", "modp/srp/4096",
+         "-----BEGIN DH PARAMETERS-----"
+         "MIICCAKCAgEA///////////JD9qiIWjCNMTGYouA3BzRKQJOCIpnzHQCC76mOxOb"
+         "IlFKCHmONATd75UZs806QxswKwpt8l8UN0/hNW1tUcJF5IW1dmJefsb0TELppjft"
+         "awv/XLb0Brft7jhr+1qJn6WunyQRfEsf5kkoZlHs5Fs9wgB8uKFjvwWY2kg2HFXT"
+         "mmkWP6j9JM9fg2VdI9yjrZYcYvNWIIVSu57VKQdwlpZtZww1Tkq8mATxdGwIyhgh"
+         "fDKQXkYuNs474553LBgOhgObJ4Oi7Aeij7XFXfBvTFLJ3ivL9pVYFxg5lUl86pVq"
+         "5RXSJhiY+gUQFXKOWoqqxC2tMxcNBFB6M6hVIavfHLpk7PuFBFjb7wqK6nFXXQYM"
+         "fbOXD4Wm4eTHq/WujNsJM9cejJTgSiVhnc7j0iYa0u5r8S/6BtmKCGTYdgJzPshq"
+         "ZFIfKxgXeyAMu+EXV3phXWx3CYjAutlG4gjiT6B05asxQ9tb/OD9EI5LgtEgqSEI"
+         "ARpyPBKnh+bXiHGaEL26WyaZwycYavTiPBqUaDS2FQvaJYPpyirUTOjbu8LbBN6O"
+         "+S6O/BQfvsqmKHxZR05rwF2ZspZPoJDDoiM7oYZRW+ftH2EpcM7i16+4G912IXBI"
+         "HNAGkSfVsFqpk7TqmI2P3cGG/7fckKbAj030Nck0BjGZ//////////8CAQU="
+         "-----END DH PARAMETERS-----");
+
    config.set("dl", "modp/ietf/6144",
          "-----BEGIN X942 DH PARAMETERS-----"
          "MIIGDAKCAwEA///////////JD9qiIWjCNMTGYouA3BzRKQJOCIpnzHQCC76mOxOb"
@@ -451,6 +488,27 @@ void set_default_dl_groups(Library_State& config)
          "jzbmIBJ//////////wIBAg=="
          "-----END X942 DH PARAMETERS-----");
 
+   config.set("dl", "modp/srp/6144",
+         "-----BEGIN DH PARAMETERS-----"
+         "MIIDCAKCAwEA///////////JD9qiIWjCNMTGYouA3BzRKQJOCIpnzHQCC76mOxOb"
+         "IlFKCHmONATd75UZs806QxswKwpt8l8UN0/hNW1tUcJF5IW1dmJefsb0TELppjft"
+         "awv/XLb0Brft7jhr+1qJn6WunyQRfEsf5kkoZlHs5Fs9wgB8uKFjvwWY2kg2HFXT"
+         "mmkWP6j9JM9fg2VdI9yjrZYcYvNWIIVSu57VKQdwlpZtZww1Tkq8mATxdGwIyhgh"
+         "fDKQXkYuNs474553LBgOhgObJ4Oi7Aeij7XFXfBvTFLJ3ivL9pVYFxg5lUl86pVq"
+         "5RXSJhiY+gUQFXKOWoqqxC2tMxcNBFB6M6hVIavfHLpk7PuFBFjb7wqK6nFXXQYM"
+         "fbOXD4Wm4eTHq/WujNsJM9cejJTgSiVhnc7j0iYa0u5r8S/6BtmKCGTYdgJzPshq"
+         "ZFIfKxgXeyAMu+EXV3phXWx3CYjAutlG4gjiT6B05asxQ9tb/OD9EI5LgtEgqSEI"
+         "ARpyPBKnh+bXiHGaEL26WyaZwycYavTiPBqUaDS2FQvaJYPpyirUTOjbu8LbBN6O"
+         "+S6O/BQfvsqmKHxZR05rwF2ZspZPoJDDoiM7oYZRW+ftH2EpcM7i16+4G912IXBI"
+         "HNAGkSfVsFqpk7TqmI2P3cGG/7fckKbAj030Nck0AoSSNsP6tNJ8cCbB1NyyYCZG"
+         "3sl1HnY9uje9+P+UBq2eUw7l2zgvQTABrrBqU+2QJ9gxF5cnsIZaiRjaPtvrz5sU"
+         "7UTObLrO1Lsb238UR+bMJUszIFFRK9evQm+49AE3jNK/WYPKAcZLkuzwMuoV0XId"
+         "A/SC185udP721V5wL0aYDIK1qEAxkAscnlnnyX++x+jzI6l6fjbMiL4PHUW3/1ha"
+         "xUvUB7IrQVSqzI9tfr9I4dgUzF7SD4A34KeXFe7ym+MoBqHVi7fF2nb1UKo9ih+/"
+         "8OsZzLGjE9Vc2lbJ7C7yljI4f+jXbjwEaAQ+j2Y/SGDuEr8tWwt0dNbmlPkebcxA"
+         "JP//////////AgEF"
+         "-----END DH PARAMETERS-----");
+
    config.set("dl", "modp/ietf/8192",
          "-----BEGIN X942 DH PARAMETERS-----"
          "MIIIDAKCBAEA///////////JD9qiIWjCNMTGYouA3BzRKQJOCIpnzHQCC76mOxOb"
@@ -498,6 +556,32 @@ void set_default_dl_groups(Library_State& config)
          "034BNyPKrHIjqzv01U8YKHE7K0pv5A+rdEBctziwZMBuzHbp7///////////AgEC"
          "-----END X942 DH PARAMETERS-----");
 
+   config.set("dl", "modp/srp/8192",
+         "-----BEGIN DH PARAMETERS-----"
+         "MIIECAKCBAEA///////////JD9qiIWjCNMTGYouA3BzRKQJOCIpnzHQCC76mOxOb"
+         "IlFKCHmONATd75UZs806QxswKwpt8l8UN0/hNW1tUcJF5IW1dmJefsb0TELppjft"
+         "awv/XLb0Brft7jhr+1qJn6WunyQRfEsf5kkoZlHs5Fs9wgB8uKFjvwWY2kg2HFXT"
+         "mmkWP6j9JM9fg2VdI9yjrZYcYvNWIIVSu57VKQdwlpZtZww1Tkq8mATxdGwIyhgh"
+         "fDKQXkYuNs474553LBgOhgObJ4Oi7Aeij7XFXfBvTFLJ3ivL9pVYFxg5lUl86pVq"
+         "5RXSJhiY+gUQFXKOWoqqxC2tMxcNBFB6M6hVIavfHLpk7PuFBFjb7wqK6nFXXQYM"
+         "fbOXD4Wm4eTHq/WujNsJM9cejJTgSiVhnc7j0iYa0u5r8S/6BtmKCGTYdgJzPshq"
+         "ZFIfKxgXeyAMu+EXV3phXWx3CYjAutlG4gjiT6B05asxQ9tb/OD9EI5LgtEgqSEI"
+         "ARpyPBKnh+bXiHGaEL26WyaZwycYavTiPBqUaDS2FQvaJYPpyirUTOjbu8LbBN6O"
+         "+S6O/BQfvsqmKHxZR05rwF2ZspZPoJDDoiM7oYZRW+ftH2EpcM7i16+4G912IXBI"
+         "HNAGkSfVsFqpk7TqmI2P3cGG/7fckKbAj030Nck0AoSSNsP6tNJ8cCbB1NyyYCZG"
+         "3sl1HnY9uje9+P+UBq2eUw7l2zgvQTABrrBqU+2QJ9gxF5cnsIZaiRjaPtvrz5sU"
+         "7UTObLrO1Lsb238UR+bMJUszIFFRK9evQm+49AE3jNK/WYPKAcZLkuzwMuoV0XId"
+         "A/SC185udP721V5wL0aYDIK1qEAxkAscnlnnyX++x+jzI6l6fjbMiL4PHUW3/1ha"
+         "xUvUB7IrQVSqzI9tfr9I4dgUzF7SD4A34KeXFe7ym+MoBqHVi7fF2nb1UKo9ih+/"
+         "8OsZzLGjE9Vc2lbJ7C7yljI4f+jXbjwEaAQ+j2Y/SGDuEr8tWwt0dNbmlPkebb4R"
+         "WXSjkm8S/uXkOHd8tqky34zYvsTQc7kxujvIMraNndMAdB+nv4r8R+0ldvaTa6Qk"
+         "ZjqrY5xa5PVoNCO0dCvxyXgjjxbL451lLeP9uL78hIrZIiIuBKQDfAcT61eoGiPw"
+         "xzRz/GRs6jBrS8vIhi+Dhd36nUt/osCH6HloMwPtW906Bis89bOieKZtKhP4P0T4"
+         "Ld8xDuB0q2o2RZfomaAlXcFk8xzFCEaFHfmrSBld7X6hsdUQvX7nTXP682vDHs+i"
+         "aDWQRvTrh5+SQAlDi0gcbNeImgAu1e44K8kZDab8Am5HlVjkR1Z36aqeMFDidlaU"
+         "38gfVuiAuW5xYMmA3Zjt09///////////wIBEw=="
+         "-----END DH PARAMETERS-----");
+
    config.set("dl", "dsa/jce/512",
          "-----BEGIN DSA PARAMETERS-----"
          "MIGdAkEA/KaCzo4Syrom78z3EQ5SbbB4sF7ey80etKII864WF64B81uRpH5t9jQT"