| SYNOPSIS |
#include <dkim.h>
DKIM_STAT dkim_sig_getcanonlen(
DKIM *dkim,
DKIM_SIGINFO *sig,
ssize_t *msglen,
ssize_t *canonlen,
ssize_t *signlen
);
Retrieve the number of bytes of message body presented for signing
or verifying, and/or the number of bytes actually signed or verified.
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| DESCRIPTION |
| Called When |
dkim_sig_getcanonlen() is called after
dkim_eom() to get the number of
bytes of message body presented for signing or verifying, and/or
the number of bytes actually signed or verified. This is used to
allow a verifier to insist on minimum signing volumes or
percentages (e.g., a verifier may decide not to trust a message which
was only partially signed). |
|
|---|
| ARGUMENTS |
| Argument | Description |
|---|
| dkim |
Message-specific handle, returned by
dkim_sign() or
dkim_verify.
|
| sig |
The DKIM_SIGINFO handle representing the signature
being evaluated.
|
| msglen |
A pointer to an ssize_t which will receive a count of
the number of bytes in the canonicalized form of the message.
This should always be the number of bytes in the message body
plus or minus whatever was required to canonicalize it (so for
"simple" canonicalization it should be roughly the exact byte count,
while for "relaxed" canonicalization it should be somewhat less).
Can be NULL if this information is not needed by the caller.
|
| canonlen |
A pointer to an ssize_t which will receive a count of
the number of bytes in the canonicalized form of the message
that were included in the signed data. If msglen and
canonlen are the same, then the entire message was signed.
If it is less, then the signer didn't sign the entire message.
A verifier can compare this value with that of msglen
to see what portion of the total message was signed by the signer.
Note that msglen and canonlen can differ even if
no signature length limit was set if, for example, there were
trailing blank lines on the message as these are always stripped.
Can be NULL if this information is not needed by the caller.
|
| signlen |
A pointer to an ssize_t which will receive the signature
length limit for this signature (i.e. the value of the "l=" tag
if one was present on the signature). If no limit was set by
the signer, a value of -1 is returned.
Can be NULL if this information is not needed by the caller.
|
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| NOTES |
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