- don't free user-supplied string (via -e)

[oweals/busybox.git] / libbb / pw_encrypt_md5.c

diff --git a/libbb/pw_encrypt_md5.c b/libbb/pw_encrypt_md5.c
index 42eb13440ed673845084ad744508a4be41eb9dac..8d0a516cf945a8454b0482ae131f0dac1bc3d5d4 100644 (file)
--- a/libbb/pw_encrypt_md5.c
+++ b/libbb/pw_encrypt_md5.c
@@ -101,7 +101,6 @@ static const unsigned char __md5__magic[] = MD5_MAGIC_STR;
  * __md5_Encodes input (uint32_t) into output (unsigned char). Assumes len is
  * a multiple of 4.
  */
-
 static void
 __md5_Encode(unsigned char *output, uint32_t *input, unsigned int len)
 {
@@ -119,7 +118,6 @@ __md5_Encode(unsigned char *output, uint32_t *input, unsigned int len)
  * __md5_Decodes input (unsigned char) into output (uint32_t). Assumes len is
  * a multiple of 4.
  */
-
 static void
 __md5_Decode(uint32_t *output, const unsigned char *input, unsigned int len)
 {
@@ -166,7 +164,6 @@ __md5_Decode(uint32_t *output, const unsigned char *input, unsigned int len)
        }
 
 /* MD5 initialization. Begins an MD5 operation, writing a new context. */
-
 static void __md5_Init(struct MD5Context *context)
 {
        context->count[0] = context->count[1] = 0;
@@ -183,7 +180,6 @@ static void __md5_Init(struct MD5Context *context)
  * operation, processing another message block, and updating the
  * context.
  */
-
 static void __md5_Update(struct MD5Context *context, const unsigned char *input, unsigned int inputLen)
 {
        unsigned int i, idx, partLen;
@@ -218,7 +214,6 @@ static void __md5_Update(struct MD5Context *context, const unsigned char *input,
 /*
  * MD5 padding. Adds padding followed by original length.
  */
-
 static void __md5_Pad(struct MD5Context *context)
 {
        unsigned char bits[8];
@@ -244,7 +239,6 @@ static void __md5_Pad(struct MD5Context *context)
  * MD5 finalization. Ends an MD5 message-digest operation, writing the
  * the message digest and zeroizing the context.
  */
-
 static void __md5_Final(unsigned char digest[16], struct MD5Context *context)
 {
        /* Do padding. */
@@ -258,7 +252,6 @@ static void __md5_Final(unsigned char digest[16], struct MD5Context *context)
 }
 
 /* MD5 basic transformation. Transforms state based on block. */
-
 static void __md5_Transform(uint32_t state[4], const unsigned char block[64])
 {
        uint32_t a, b, c, d, x[16];
@@ -501,13 +494,14 @@ static void __md5_Transform(uint32_t state[4], const unsigned char block[64])
 }
 
 
-static void
-__md5_to64(char *s, unsigned long v, int n)
+static char*
+__md5_to64(char *s, unsigned v, int n)
 {
        while (--n >= 0) {
                *s++ = ascii64[v & 0x3f];
                v >>= 6;
        }
+       return s;
 }
 
 /*
@@ -515,17 +509,16 @@ __md5_to64(char *s, unsigned long v, int n)
  *
  * Use MD5 for what it is best at...
  */
-#define MD5_OUT_BUFSIZE 120
-
+#define MD5_OUT_BUFSIZE 36
 static char *
-md5_crypt(char passwd[120], const unsigned char *pw, const unsigned char *salt)
+NOINLINE
+md5_crypt(char passwd[MD5_OUT_BUFSIZE], const unsigned char *pw, const unsigned char *salt)
 {
        const unsigned char *sp, *ep;
        char *p;
        unsigned char final[17];        /* final[16] exists only to aid in looping */
        int sl, pl, i, pw_len;
        struct MD5Context ctx, ctx1;
-       unsigned long l;
 
        /* Refine the Salt first */
        sp = salt;
@@ -578,7 +571,6 @@ md5_crypt(char passwd[120], const unsigned char *pw, const unsigned char *salt)
        passwd[2] = '$';
        strncpy(passwd + 3, (char*)sp, sl);
        passwd[sl + 3] = '$';
-       passwd[sl + 4] = '\0';
 
        __md5_Final(final, &ctx);
 
@@ -607,15 +599,15 @@ md5_crypt(char passwd[120], const unsigned char *pw, const unsigned char *salt)
                __md5_Final(final, &ctx1);
        }
 
-       p = passwd + sl + 4; /*strlen(passwd);*/
+       p = passwd + sl + 4; /* 12 bytes max (sl is up to 8 bytes) */
 
+       /* Add 5*4+2 = 22 bytes of hash, + NUL byte. */
        final[16] = final[5];
        for (i = 0; i < 5; i++) {
-               l = (final[i] << 16) | (final[i+6] << 8) | final[i+12];
-               __md5_to64(p, l, 4); p += 4;
+               unsigned l = (final[i] << 16) | (final[i+6] << 8) | final[i+12];
+               p = __md5_to64(p, l, 4);
        }
-       l = final[11];
-       __md5_to64(p, l, 2); p += 2;
+       p = __md5_to64(p, final[11], 2);
        *p = '\0';
 
        /* Don't leave anything around in vm they could use. */