IV is short for 'initialization vector'

Author: sjaeckel

doc/crypt.tex

@@ -781,7 +781,7 @@ \subsection{Notes}
 \subsection{Background}
 A typical symmetric block cipher can be used in chaining modes to effectively encrypt messages larger than the block
 size of the cipher.  Given a key $k$, a plaintext $P$ and a cipher $E$ we shall denote the encryption of the block
-$P$ under the key $k$ as $E_k(P)$.  In some modes there exists an initial vector denoted as $C_{-1}$.
+$P$ under the key $k$ as $E_k(P)$.  In some modes there exists an initialization vector denoted as $C_{-1}$.
 
 \subsubsection{ECB Mode}
 \index{ECB mode}
@@ -799,19 +799,19 @@ \subsubsection{CBC Mode}
 \begin{equation}
 C_i = E_k(P_i \oplus C_{i - 1})
 \end{equation}
-It is important that the initial vector be unique and preferably random for each message encrypted under the same key.
+It is important that the initialization vector be unique and preferably random for each message encrypted under the same key.
 
 \subsubsection{CTR Mode}
 \index{CTR mode}
-CTR or Counter Mode is a mode which only uses the encryption function of the cipher.  Given a initial vector which is
+CTR or Counter Mode is a mode which only uses the encryption function of the cipher.  Given a initialization vector which is
 treated as a large binary counter the CTR mode is given as:
 \begin{eqnarray}
 C_{-1} = C_{-1} + 1\mbox{ }(\mbox{mod }2^W) \nonumber \\
 C_i = P_i \oplus E_k(C_{-1})
 \end{eqnarray}
-Where $W$ is the size of a block in bits (e.g. 64 for Blowfish).  As long as the initial vector is random for each message
+Where $W$ is the size of a block in bits (e.g. 64 for Blowfish).  As long as the initialization vector is random for each message
 encrypted under the same key replay and swap attacks are infeasible.  CTR mode may look simple but it is as secure
-as the block cipher is under a chosen plaintext attack (provided the initial vector is unique).
+as the block cipher is under a chosen plaintext attack (provided the initialization vector is unique).
 
 \subsubsection{CFB Mode}
 \index{CFB mode}
@@ -822,7 +822,7 @@ \subsubsection{CFB Mode}
 \end{eqnarray}
 Note that in this library the output feedback width is equal to the size of the block cipher.  That is this mode is used
 to encrypt whole blocks at a time.  However, the library will buffer data allowing the user to encrypt or decrypt partial
-blocks without a delay.  When this mode is first setup it will initially encrypt the initial vector as required.
+blocks without a delay.  When this mode is first setup it will initially encrypt the initialization vector as required.
 
 \subsubsection{OFB Mode}
 \index{OFB mode}
@@ -1012,7 +1012,7 @@ \subsection{Examples}
    /* start up CTR mode */
    if ((err = ctr_start(
         find_cipher("twofish"), /* index of desired cipher */
-                            IV, /* the initial vector */
+                            IV, /* the initialization vector */
                            key, /* the secret key */
                             16, /* length of secret key (16 bytes) */
                              0, /* 0 == default # of rounds */
@@ -1786,7 +1786,7 @@ \subsection{Initialization}
 as \textit{aadlen}.
 
 \subsection{Nonce Vector}
-After the state has been initialized (or reset) the next step is to add the session (or packet) initial vector.  It should be unique per packet encrypted.
+After the state has been initialized (or reset) the next step is to add the session (or packet) initialization vector.  It should be unique per packet encrypted.
 
 \index{ccm\_add\_nonce()}
 \begin{verbatim}
@@ -1973,7 +1973,7 @@ \subsection{Example Usage}
 however, unlike EAX it cannot accept \textit{additional authentication data} (meta--data) after plaintext has been processed.  This mode also only works with
 block ciphers with a 16--byte block.
 
-A GCM stream is meant to be processed in three modes, one after another.  First, the initial vector (per session) data is processed.  This should be
+A GCM stream is meant to be processed in three modes, one after another.  First, the initialization vector (per session) data is processed.  This should be
 unique to every session.  Next, the the optional additional authentication data is processed, and finally the plaintext (or ciphertext depending on the direction).
 
 \subsection{Initialization}
@@ -1989,16 +1989,16 @@ \subsection{Initialization}
 This initializes the GCM state \textit{gcm} for the given cipher indexed by \textit{cipher}, with a secret key \textit{key} of length \textit{keylen} octets.  The cipher
 chosen must have a 16--byte block size (e.g., AES).
 
-\subsection{Initial Vector}
-After the state has been initialized (or reset) the next step is to add the session (or packet) initial vector.  It should be unique per packet encrypted.
+\subsection{Initialization Vector}
+After the state has been initialized (or reset) the next step is to add the session (or packet) initialization vector.  It should be unique per packet encrypted.
 
 \index{gcm\_add\_iv()}
 \begin{verbatim}
 int gcm_add_iv(          gcm_state *gcm,
                const unsigned char *IV,
                      unsigned long  IVlen);
 \end{verbatim}
-This adds the initial vector octets from \textit{IV} of length \textit{IVlen} to the GCM state \textit{gcm}.  You can call this function as many times as required
+This adds the initialization vector octets from \textit{IV} of length \textit{IVlen} to the GCM state \textit{gcm}.  You can call this function as many times as required
 to process the entire IV.
 
 Note: the GCM protocols provides a \textit{shortcut} for 12--byte IVs where no pre-processing is to be done.  If you want to minimize per packet latency it is ideal
@@ -2193,16 +2193,16 @@ \subsection{Initialization}
 This initializes the ChaCha20--Poly1305 state \textit{st} with a secret key \textit{key} of length \textit{keylen}
 octets (valid lengths: 32 or 16).
 
-\subsection{Initial Vector}
-After the state has been initialized the next step is to add the initial vector.
+\subsection{Initialization Vector}
+After the state has been initialized the next step is to add the initialization vector.
 
 \index{chacha20poly1305\_setiv()}
 \begin{verbatim}
 int chacha20poly1305_setiv(chacha20poly1305_state *st,
                               const unsigned char *iv,
                                     unsigned long  ivlen);
 \end{verbatim}
-This adds the initial vector from \textit{iv} of length \textit{ivlen} octects (valid lengths: 8 or 12) to
+This adds the initialization vector from \textit{iv} of length \textit{ivlen} octects (valid lengths: 8 or 12) to
 the ChaCha20--Poly1305 state \textit{st}.
 
 \index{chacha20poly1305\_setiv\_rfc7905()}
@@ -2212,7 +2212,7 @@ \subsection{Initial Vector}
                                             unsigned long  ivlen,
                                                   ulong64  sequence_number);
 \end{verbatim}
-This also adds the initial vector from \textit{iv} of length \textit{ivlen} octects (valid lengths: 8 or 12) to
+This also adds the initialization vector from \textit{iv} of length \textit{ivlen} octects (valid lengths: 8 or 12) to
 the state \textit{st} but it also incorporates 64bit \textit{sequence\_number} into IV as described in RFC7905.
 
 You can call only one of \textit{chacha20poly1305\_setiv} or \textit{chacha20poly1305\_setiv\_rfc7905}.
@@ -6163,7 +6163,7 @@ \subsection{Algorithm One}
 \subsection{Algorithm Two}
 
 Algorithm Two is the recommended algorithm for this task.  It allows variable length salts, and can produce outputs larger than the
-hash functions output.  As such, it can easily be used to derive session keys for ciphers and MACs as well initial vectors as required
+hash functions output.  As such, it can easily be used to derive session keys for ciphers and MACs as well initialization vectors as required
 from a single password and invocation of this algorithm.
 
 \index{pkcs\_5\_alg2()}
@@ -7295,8 +7295,8 @@ \chapter{Optimizations}
    /** Accelerated GCM packet (one shot)
        @param key        The secret key
        @param keylen     The length of the secret key
-       @param IV         The initial vector
-       @param IVlen      The length of the initial vector
+       @param IV         The initialization vector
+       @param IVlen      The length of the initialization vector
        @param adata      The additional authentication data (header)
        @param adatalen   The length of the adata
        @param pt         The plaintext
@@ -7412,7 +7412,7 @@ \subsubsection{Accelerated ECB}
 
 \subsubsection{Accelerated CBC}
 These two functions are meant for accelerated CBC encryption.  These functions are accessed through the accel\_cbc\_encrypt and accel\_cbc\_decrypt pointers.
-The \textit{blocks} value is the number of complete blocks to process.  The \textit{IV} is the CBC initial vector.  It is an input upon calling this function and must be
+The \textit{blocks} value is the number of complete blocks to process.  The \textit{IV} is the CBC initialization vector.  It is an input upon calling this function and must be
 updated by the function before returning.
 
 \subsubsection{Accelerated CTR}

src/encauth/chachapoly/chacha20poly1305_memory.c

@@ -15,8 +15,8 @@
   Process an entire GCM packet in one call.
   @param key               The secret key
   @param keylen            The length of the secret key
-  @param iv                The initial vector
-  @param ivlen             The length of the initial vector
+  @param iv                The initialization vector
+  @param ivlen             The length of the initialization vector
   @param aad               The additional authentication data (header)
   @param aadlen            The length of the aad
   @param in                The plaintext

src/encauth/gcm/gcm_memory.c

@@ -20,8 +20,8 @@
   @param cipher            Index of cipher to use
   @param key               The secret key
   @param keylen            The length of the secret key
-  @param IV                The initial vector
-  @param IVlen             The length of the initial vector
+  @param IV                The initialization vector
+  @param IVlen             The length of the initialization vector
   @param adata             The additional authentication data (header)
   @param adatalen          The length of the adata
   @param pt                The plaintext

src/headers/tomcrypt_cipher.h

@@ -499,8 +499,8 @@ extern struct ltc_cipher_descriptor {
    /** Accelerated GCM packet (one shot)
        @param key        The secret key
        @param keylen     The length of the secret key
-       @param IV         The initial vector
-       @param IVlen      The length of the initial vector
+       @param IV         The initialization vector
+       @param IVlen      The length of the initialization vector
        @param adata      The additional authentication data (header)
        @param adatalen   The length of the adata
        @param pt         The plaintext

src/mac/hmac/hmac_init.c

@@ -75,7 +75,7 @@ int hmac_init(hmac_state *hmac, int hash, const unsigned char *key, unsigned lon
        zeromem((hmac->key) + keylen, (size_t)(LTC_HMAC_BLOCKSIZE - keylen));
     }
 
-    /* Create the initial vector for step (3) */
+    /* Create the initialization vector for step (3) */
     for(i=0; i < LTC_HMAC_BLOCKSIZE;   i++) {
        buf[i] = hmac->key[i] ^ 0x36;
     }

src/modes/cbc/cbc_getiv.c

@@ -16,9 +16,9 @@
 #ifdef LTC_CBC_MODE
 
 /**
-   Get the current initial vector
-   @param IV   [out] The destination of the initial vector
-   @param len  [in/out]  The max size and resulting size of the initial vector
+   Get the current initialization vector
+   @param IV   [out] The destination of the initialization vector
+   @param len  [in/out]  The max size and resulting size of the initialization vector
    @param cbc  The CBC state
    @return CRYPT_OK if successful
 */

src/modes/cbc/cbc_setiv.c

@@ -17,8 +17,8 @@
 #ifdef LTC_CBC_MODE
 
 /**
-   Set an initial vector
-   @param IV   The initial vector
+   Set an initialization vector
+   @param IV   The initialization vector
    @param len  The length of the vector (in octets)
    @param cbc  The CBC state
    @return CRYPT_OK if successful

src/modes/cbc/cbc_start.c

@@ -18,7 +18,7 @@
 /**
    Initialize a CBC context
    @param cipher      The index of the cipher desired
-   @param IV          The initial vector
+   @param IV          The initialization vector
    @param key         The secret key
    @param keylen      The length of the secret key (octets)
    @param num_rounds  Number of rounds in the cipher desired (0 for default)

src/modes/cfb/cfb_getiv.c

@@ -16,9 +16,9 @@
 #ifdef LTC_CFB_MODE
 
 /**
-   Get the current initial vector
-   @param IV   [out] The destination of the initial vector
-   @param len  [in/out]  The max size and resulting size of the initial vector
+   Get the current initialization vector
+   @param IV   [out] The destination of the initialization vector
+   @param len  [in/out]  The max size and resulting size of the initialization vector
    @param cfb  The CFB state
    @return CRYPT_OK if successful
 */

src/modes/cfb/cfb_setiv.c

@@ -16,8 +16,8 @@
 #ifdef LTC_CFB_MODE
 
 /**
-   Set an initial vector
-   @param IV   The initial vector
+   Set an initialization vector
+   @param IV   The initialization vector
    @param len  The length of the vector (in octets)
    @param cfb  The CFB state
    @return CRYPT_OK if successful