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authorbrain <brain@e03df62e-2008-0410-955e-edbf42e46eb7>2006-08-06 21:03:41 +0000
committerbrain <brain@e03df62e-2008-0410-955e-edbf42e46eb7>2006-08-06 21:03:41 +0000
commitafb5e20d25f3be6c8854cbd3497ea04b2edf14a5 (patch)
treeac915d3ff4581868220f6846bc0d9f16a4afaf0a
parentcf8a24cd6baf4f8b101fc1d1edf6c0046d2b9b09 (diff)
Tidy up comments
git-svn-id: http://svn.inspircd.org/repository/trunk/inspircd@4748 e03df62e-2008-0410-955e-edbf42e46eb7
-rw-r--r--src/aes.cpp115
1 files changed, 62 insertions, 53 deletions
diff --git a/src/aes.cpp b/src/aes.cpp
index 033d8beb2..8ec6dd3bc 100644
--- a/src/aes.cpp
+++ b/src/aes.cpp
@@ -14,8 +14,9 @@
* ---------------------------------------------------
*/
-// Based on existing implementations of the industry standard AES algorithms
-// in the public domain.
+/* Based on existing implementations of the industry
+ * standard AES algorithms in the public domain.
+ */
#include <cstring>
#include "aes.h"
@@ -932,24 +933,31 @@ const int AES::sm_shifts[3][4][2] =
{ {0, 0}, {1, 7}, {3, 5}, {4, 4} }
};
-//Null chain
+/**
+ * Null chain
+ */
char const* AES::sm_chain0 = "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0";
-//CONSTRUCTOR
+/**
+ * CONSTRUCTOR
+ */
AES::AES() : m_bKeyInit(false)
{
}
-//DESTRUCTOR
+/**
+ * DESTRUCTOR
+ */
AES::~AES()
{
}
-//Expand a user-supplied key material into a session key.
-// key - The 128/192/256-bit user-key to use.
-// chain - initial chain block for CBC and CFB modes.
-// keylength - 16, 24 or 32 bytes
-// blockSize - The block size in bytes of this Rijndael (16, 24 or 32 bytes).
+/** Expand a user-supplied key material into a session key.
+ * @param key The 128/192/256-bit user-key to use.
+ * @param chain initial chain block for CBC and CFB modes.
+ * @param keylength 16, 24 or 32 bytes
+ * @param blockSize The block size in bytes of this Rijndael (16, 24 or 32 bytes).
+ */
void AES::MakeKey(char const* key, char const* chain, int keylength, int blockSize)
{
if (NULL == key)
@@ -960,10 +968,10 @@ void AES::MakeKey(char const* key, char const* chain, int keylength, int blockSi
return;
m_keylength = keylength;
m_blockSize = blockSize;
- //Initialize the chain
+ /* Initialize the chain */
memcpy(m_chain0, chain, m_blockSize);
memcpy(m_chain, chain, m_blockSize);
- //Calculate Number of Rounds
+ /* Calculate Number of Rounds */
switch (m_keylength)
{
case 16:
@@ -974,7 +982,7 @@ void AES::MakeKey(char const* key, char const* chain, int keylength, int blockSi
m_iROUNDS = (m_blockSize != 32) ? 12 : 14;
break;
- default: // 32 bytes = 256 bits
+ default: /* 32 bytes = 256 bits */
m_iROUNDS = 14;
}
int BC = m_blockSize / 4;
@@ -991,7 +999,7 @@ void AES::MakeKey(char const* key, char const* chain, int keylength, int blockSi
}
int ROUND_KEY_COUNT = (m_iROUNDS + 1) * BC;
int KC = m_keylength/4;
- //Copy user material bytes into temporary ints
+ /* Copy user material bytes into temporary ints */
int* pi = tk;
char const* pc = key;
for (i=0; i<KC; i++)
@@ -1001,7 +1009,7 @@ void AES::MakeKey(char const* key, char const* chain, int keylength, int blockSi
*pi |= (unsigned char)*(pc++) << 8;
*(pi++) |= (unsigned char)*(pc++);
}
- //Copy values into round key arrays
+ /* Copy values into round key arrays */
int t = 0;
for (j=0; (j<KC)&&(t<ROUND_KEY_COUNT); j++,t++)
{
@@ -1011,7 +1019,7 @@ void AES::MakeKey(char const* key, char const* chain, int keylength, int blockSi
int tt, rconpointer = 0;
while (t < ROUND_KEY_COUNT)
{
- //Extrapolate using phi (the round key evolution function)
+ /* Extrapolate using phi (the round key evolution function) */
tt = tk[KC-1];
tk[0] ^= (sm_S[(tt >> 16) & 0xFF] & 0xFF) << 24 ^
(sm_S[(tt >> 8) & 0xFF] & 0xFF) << 16 ^
@@ -1033,14 +1041,14 @@ void AES::MakeKey(char const* key, char const* chain, int keylength, int blockSi
for (j = KC/2, i=j+1; i<KC; )
tk[i++] ^= tk[j++];
}
- //Copy values into round key arrays
+ /* Copy values into round key arrays */
for (j=0; (j<KC) && (t<ROUND_KEY_COUNT); j++, t++)
{
m_Ke[t/BC][t%BC] = tk[j];
m_Kd[m_iROUNDS - (t/BC)][t%BC] = tk[j];
}
}
- //Inverse MixColumn where needed
+ /* Inverse MixColumn where needed */
for (int r=1; r<m_iROUNDS; r++)
for (j=0; j<BC; j++)
{
@@ -1053,10 +1061,10 @@ void AES::MakeKey(char const* key, char const* chain, int keylength, int blockSi
m_bKeyInit = true;
}
-//Convenience method to encrypt exactly one block of plaintext, assuming
-//Rijndael's default block size (128-bit).
-// in - The plaintext
-// result - The ciphertext generated from a plaintext using the key
+/** Convenience method to encrypt exactly one block of plaintext, assuming Rijndael's default block size (128-bit).
+ * @param in The plaintext
+ * @returns The ciphertext generated from a plaintext using the key
+ */
void AES::DefEncryptBlock(char const* in, char* result)
{
if (m_bKeyInit == false)
@@ -1079,7 +1087,7 @@ void AES::DefEncryptBlock(char const* in, char* result)
t3 |= ((unsigned char)*(in++) << 8);
(t3 |= (unsigned char)*(in++)) ^= Ker[3];
int a0, a1, a2, a3;
- //Apply Round Transforms
+ /* Apply round transforms */
for (int r = 1; r < m_iROUNDS; r++)
{
Ker = m_Ke[r];
@@ -1104,7 +1112,7 @@ void AES::DefEncryptBlock(char const* in, char* result)
t2 = a2;
t3 = a3;
}
- //Last Round is special
+ /* Last round is special */
Ker = m_Ke[m_iROUNDS];
int tt = Ker[0];
result[0] = sm_S[(t0 >> 24) & 0xFF] ^ (tt >> 24);
@@ -1128,10 +1136,10 @@ void AES::DefEncryptBlock(char const* in, char* result)
result[15] = sm_S[t2 & 0xFF] ^ tt;
}
-//Convenience method to decrypt exactly one block of plaintext, assuming
-//Rijndael's default block size (128-bit).
-// in - The ciphertext.
-// result - The plaintext generated from a ciphertext using the session key.
+/** Convenience method to decrypt exactly one block of plaintext, assuming Rijndael's default block size (128-bit).
+ * @param in The ciphertext.
+ * @return The plaintext generated from a ciphertext using the session key.
+ */
void AES::DefDecryptBlock(char const* in, char* result)
{
if (m_bKeyInit == false)
@@ -1154,7 +1162,7 @@ void AES::DefDecryptBlock(char const* in, char* result)
t3 |= ((unsigned char)*(in++) << 8);
(t3 |= (unsigned char)*(in++)) ^= Kdr[3];
int a0, a1, a2, a3;
- for (int r = 1; r < m_iROUNDS; r++) // apply round transforms
+ for (int r = 1; r < m_iROUNDS; r++) /* apply round transforms */
{
Kdr = m_Kd[r];
a0 = (sm_T5[(t0 >> 24) & 0xFF] ^
@@ -1178,7 +1186,7 @@ void AES::DefDecryptBlock(char const* in, char* result)
t2 = a2;
t3 = a3;
}
- //Last Round is special
+ /* Last round is special */
Kdr = m_Kd[m_iROUNDS];
int tt = Kdr[0];
result[ 0] = sm_Si[(t0 >> 24) & 0xFF] ^ (tt >> 24);
@@ -1202,9 +1210,10 @@ void AES::DefDecryptBlock(char const* in, char* result)
result[15] = sm_Si[ t0 & 0xFF] ^ tt;
}
-//Encrypt exactly one block of plaintext.
-// in - The plaintext.
-// result - The ciphertext generated from a plaintext using the key.
+/** Encrypt exactly one block of plaintext.
+ * @param in The plaintext.
+ * @return The ciphertext generated from a plaintext using the key.
+ */
void AES::EncryptBlock(char const* in, char* result)
{
if (m_bKeyInit == false)
@@ -1219,7 +1228,7 @@ void AES::EncryptBlock(char const* in, char* result)
int s1 = sm_shifts[SC][1][0];
int s2 = sm_shifts[SC][2][0];
int s3 = sm_shifts[SC][3][0];
- //Temporary Work Arrays
+ /* Temporary work arrays */
int i;
int tt;
int* pi = t;
@@ -1230,7 +1239,7 @@ void AES::EncryptBlock(char const* in, char* result)
*pi |= ((unsigned char)*(in++) << 8);
(*(pi++) |= (unsigned char)*(in++)) ^= m_Ke[0][i];
}
- //Apply Round Transforms
+ /* Apply round transforms */
for (int r=1; r<m_iROUNDS; r++)
{
for (i=0; i<BC; i++)
@@ -1241,7 +1250,7 @@ void AES::EncryptBlock(char const* in, char* result)
memcpy(t, a, 4*BC);
}
int j;
- //Last Round is Special
+ /* Last round is special */
for (i=0,j=0; i<BC; i++)
{
tt = m_Ke[m_iROUNDS][i];
@@ -1252,9 +1261,10 @@ void AES::EncryptBlock(char const* in, char* result)
}
}
-//Decrypt exactly one block of ciphertext.
-// in - The ciphertext.
-// result - The plaintext generated from a ciphertext using the session key.
+/** Decrypt exactly one block of ciphertext.
+ * @param inThe ciphertext.
+ * @return The plaintext generated from a ciphertext using the session key.
+ */
void AES::DecryptBlock(char const* in, char* result)
{
if (m_bKeyInit == false)
@@ -1269,7 +1279,7 @@ void AES::DecryptBlock(char const* in, char* result)
int s1 = sm_shifts[SC][1][1];
int s2 = sm_shifts[SC][2][1];
int s3 = sm_shifts[SC][3][1];
- //Temporary Work Arrays
+ /* Temporary work arrays */
int i;
int tt;
int* pi = t;
@@ -1280,7 +1290,7 @@ void AES::DecryptBlock(char const* in, char* result)
*pi |= ((unsigned char)*(in++) << 8);
(*(pi++) |= (unsigned char)*(in++)) ^= m_Kd[0][i];
}
- //Apply Round Transforms
+ /* Apply round transforms */
for (int r=1; r<m_iROUNDS; r++)
{
for (i=0; i<BC; i++)
@@ -1291,7 +1301,7 @@ void AES::DecryptBlock(char const* in, char* result)
memcpy(t, a, 4*BC);
}
int j;
- //Last Round is Special
+ /* Last round is special */
for (i=0,j=0; i<BC; i++)
{
tt = m_Kd[m_iROUNDS][i];
@@ -1306,13 +1316,13 @@ void AES::Encrypt(char const* in, char* result, size_t n, int iMode)
{
if (m_bKeyInit == false)
return;
- //n should be > 0 and multiple of m_blockSize
+ /* n should be > 0 and multiple of m_blockSize */
if (n == 0 || n%m_blockSize!=0)
return;
unsigned int i;
char const* pin;
char* presult;
- if (CBC == iMode) //CBC mode, using the Chain
+ if (CBC == iMode) /* CBC mode, using the chain */
{
for (i=0,pin=in,presult=result; i<n/m_blockSize; i++)
{
@@ -1323,7 +1333,7 @@ void AES::Encrypt(char const* in, char* result, size_t n, int iMode)
presult += m_blockSize;
}
}
- else if (CFB == iMode) //CFB mode, using the Chain
+ else if (CFB == iMode) /* CFB mode, using the chain */
{
for (i=0,pin=in,presult=result; i<n/m_blockSize; i++)
{
@@ -1334,7 +1344,7 @@ void AES::Encrypt(char const* in, char* result, size_t n, int iMode)
presult += m_blockSize;
}
}
- else //ECB mode, not using the Chain
+ else /* ECB mode, not using the chain */
{
for (i=0,pin=in,presult=result; i<n/m_blockSize; i++)
{
@@ -1349,13 +1359,13 @@ void AES::Decrypt(char const* in, char* result, size_t n, int iMode)
{
if (m_bKeyInit == false)
return;
- //n should be > 0 and multiple of m_blockSize
+ /* n should be > 0 and multiple of m_blockSize */
if (n == 0 || n%m_blockSize!=0)
return;
unsigned int i;
char const* pin;
char* presult;
- if (CBC == iMode) //CBC mode, using the Chain
+ if (CBC == iMode) /* CBC mode, using the chain */
{
for (i=0,pin=in,presult=result; i<n/m_blockSize; i++)
{
@@ -1366,19 +1376,18 @@ void AES::Decrypt(char const* in, char* result, size_t n, int iMode)
presult += m_blockSize;
}
}
- else if (CFB == iMode) //CFB mode, using the Chain, not using Decrypt()
+ else if (CFB == iMode) /* CFB mode, using the chain, not using Decrypt() */
{
for (i=0,pin=in,presult=result; i<n/m_blockSize; i++)
{
EncryptBlock(m_chain, presult);
- //memcpy(presult, pin, m_blockSize);
Xor(presult, pin);
memcpy(m_chain, pin, m_blockSize);
pin += m_blockSize;
presult += m_blockSize;
}
}
- else //ECB mode, not using the Chain
+ else /* ECB mode, not using the Chain */
{
for (i=0,pin=in,presult=result; i<n/m_blockSize; i++)
{
@@ -1408,7 +1417,7 @@ static const char base64val[] = {
#define DECODE64(c) (c < 128 ? base64val[c] : BAD)
void to64frombits(unsigned char *out, const unsigned char *in, int inlen)
-/* raw bytes in quasi-big-endian order to base 64 string (NUL-terminated) */
+/* Raw bytes to base 64 string (NUL-terminated) */
{
for (; inlen >= 3; inlen -= 3)
{
@@ -1434,7 +1443,7 @@ void to64frombits(unsigned char *out, const unsigned char *in, int inlen)
}
int from64tobits(char *out, const char *in, int maxlen)
-/* base 64 to raw bytes in quasi-big-endian order, returning count of bytes */
+/* base 64 to raw bytes, returning count of bytes */
/* maxlen limits output buffer size, set to zero to ignore */
{
int len = 0;