Auth Error with AWS SES

[leviouwendijk]

Hi, I've been trying an implementation using AWS SMTP credentials (which rejects .plain authentication). But it seems not to work, regardless of what I try:

Bad response received for command. command: (), response: 535 AUTH failed

Main implementations I tried:

        let smtp = SMTP(
            hostname: host,
            email: user,
            password: password,
            port: 587,
            tlsMode: .requireSTARTTLS,
            authMethods: [.login]
        )

        let smtp = SMTP(
            hostname: host,
            email: user,
            password: password,
            port: 465,
            tlsMode: .requireTLS,
            authMethods: [.login]
        )

Both fail the same with [.cramMD5].

When I use swaks, everything works fine:

swaks --to "$TO" \
    --cc "$CC" \
    --from "$FROM" \
    --header "$FROM_HEADER" \
    --header "$REPLY_TO" \
    --server "$SMTP_SERVER" \
    --port "$SMTP_PORT" \
    --auth LOGIN \
    --auth-user "$SMTP_USER" \
    --auth-password "$SMTP_PASS" \
    --tls \
    --header "Subject: $SUBJECT" \
    --header "Content-Type: text/html" \
    --body $BODY \
    --attach $ATTACHMENT --attach-type "application/pdf"

Not sure what Swift-SMTP and swaks are doing differently under the hood.

Any ideas why this auth is failing?