Sanitize php mail inbox

Sanitizing a PHP mail inbox involves cleaning and processing the email data to prevent potential security threats and ensure the integrity of the data. Here are some steps to sanitize a PHP mail inbox:

1. Validate email addresses: Use a regular expression to validate the email addresses in the inbox. This can help prevent malicious emails from being processed.
2. Strip HTML tags: Remove any HTML tags from the email bodies to prevent cross-site scripting (XSS) attacks.
3. Remove special characters: Remove any special characters, such as <, >, &, and ;, from the email bodies to prevent code injection attacks.
4. Decode special characters: Decode any special characters, such as %, +, and =, from the email bodies to prevent code injection attacks.
5. Remove attachments: Remove any attachments from the emails to prevent potential security threats.
6. Check for spam: Use a spam filtering library, such as SpamAssassin, to check the emails for spam and remove them if necessary.
7. Check for viruses: Use an antivirus library, such as ClamAV, to scan the emails for viruses and remove them if necessary.
8. Remove duplicate emails: Remove any duplicate emails from the inbox to prevent data duplication.
9. Remove emails with invalid headers: Remove any emails with invalid headers, such as missing or malformed headers, to prevent potential security threats.
10. Log and audit: Log and audit all email processing activities to ensure accountability and detect any potential security threats.

Here is an example of how you can sanitize a PHP mail inbox using the imap extension:

<?php

// Connect to the mail server
$imap = imap_open('{imap.gmail.com:993/imap/ssl}INBOX', 'your_email', 'your_password');

// Fetch all emails in the inbox
$mails = imap_search($imap, 'ALL');

// Loop through each email
foreach ($mails as $mail) {
    // Fetch the email headers
    $headers = imap_header($imap, $mail);

    // Validate the email address
    if (!preg_match('/^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$/', $headers->from[0]->mailbox)) {
        imap_delete($imap, $mail);
        continue;
    }

    // Strip HTML tags
    $body = imap_body($imap, $mail);
    $body = strip_tags($body);

    // Remove special characters
    $body = preg_replace('/[^\w\s]/', '', $body);

    // Decode special characters
    $body = html_entity_decode($body, ENT_QUOTES, 'UTF-8');

    // Remove attachments
    imap_fetchstructure($imap, $mail);
    if (isset($structure->parts)) {
        foreach ($structure->parts as $part) {
            if ($part->disposition == 'attachment') {
                imap_delete($imap, $mail);
                break;
            }
        }
    }

    // Check for spam
    $spam_score = spamassassin_score($body);
    if ($spam_score > 5) {
        imap_delete($imap, $mail);
        continue;
    }

    // Check for viruses
    $virus_score = clamav_scan($body);
    if ($virus_score > 5) {
        imap_delete($imap, $mail);
        continue;
    }

    // Remove duplicate emails
    $duplicate = false;
    foreach (imap_search($imap, 'SUBJECT "'. $headers->subject. '"') as $duplicate_mail) {
        if ($duplicate_mail == $mail) {
            $duplicate = true;
            break;
        }
    }
    if ($duplicate) {
        imap_delete($imap, $mail);
        continue;
    }

    // Remove emails with invalid headers
    if (!isset($headers->from[0]->mailbox) ||!isset($headers->from[0]->host)) {
        imap_delete($imap, $mail);
        continue;
    }

    // Log and audit
    $log = 'Email processed: '. $headers->subject. ' from '. $headers->from[0]->mailbox. ' at '. date('Y-m-d H:i:s');
    file_put_contents('email_log.txt', $log. "\n", FILE_APPEND);
}

// Close the connection
imap_close($imap);

?>

Note that this is just an example and you should adjust the code to fit your specific needs. Additionally, you should ensure that you have the necessary permissions and access to the mail server to perform these operations.