How to calculate a the files md5 in c++?

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OriginalGriff · Answer 1 · 2011-06-14T23:49:00

Solution 1

You didn't search too hard then, did you?

I tried using your subject line as a search term and got here straight away: Use Windows Crypto API to calculate a MD5 string.[^]

Posted 14-Jun-11 23:49pm

OriginalGriff

Comments

Sergey Alexandrovich Kryukov 15-Jun-11 20:02pm

Sure, a 5.
--SA

barneyman · Answer 2 · 2011-06-15T16:52:00

There's an easier alternative than spinning up the full crypto; have a look at the Message Digest functions[^]

C#

typedef struct {
    ULONG i[2];
    ULONG buf[4];
    unsigned char in[64];
    unsigned char digest[16];
} MD5_CTX;

typedef void (_stdcall *MD5Final)(MD5_CTX* context);
typedef void (_stdcall *MD5Init)(MD5_CTX* context);
typedef void (_stdcall *MD5Update)(MD5_CTX* context,unsigned char* input,unsigned int inlen);

Do a LoadLibrary("cryptdll.dll"), GetProcAddress() for each of the three functions, call MD5Init(), MD5Update() as many times required, then MD5Final(), and FreeLibrary()