# syntax=docker/dockerfile:1.4
# Base image with net-snmp 5.9.5.2 compiled from source
# Alpine 3.23 ships 5.9.4 which has segfault bugs in varbind construction
# and buffer overflows in octet string handling.
#
# Build and push with:
#   docker buildx build -f Dockerfile.netsnmp --platform linux/amd64,linux/arm64 \
#     -t ghcr.io/towerops-app/netsnmp-alpine:5.9.5.2 --push .
#
# Or use the GitHub Actions workflow: .github/workflows/netsnmp-base.yml

FROM alpine:3.23 AS builder

ARG NETSNMP_VERSION=5.9.5.2

# Install build dependencies
RUN apk add --no-cache \
    gcc \
    g++ \
    make \
    musl-dev \
    openssl-dev \
    linux-headers \
    perl \
    curl \
    file

# Download and extract net-snmp source
RUN curl -fsSL "https://downloads.sourceforge.net/project/net-snmp/net-snmp/${NETSNMP_VERSION}/net-snmp-${NETSNMP_VERSION}.tar.gz" \
    -o /tmp/net-snmp.tar.gz && \
    tar xzf /tmp/net-snmp.tar.gz -C /tmp && \
    rm /tmp/net-snmp.tar.gz

WORKDIR /tmp/net-snmp-${NETSNMP_VERSION}

# Configure with minimal features (we only need libnetsnmp)
RUN ./configure \
    --prefix=/usr \
    --sysconfdir=/etc \
    --with-defaults \
    --with-openssl \
    --enable-shared \
    --enable-static \
    --disable-applications \
    --disable-manuals \
    --disable-scripts \
    --without-perl-modules \
    --without-python-modules \
    --disable-embedded-perl \
    --with-default-snmp-version=3

# Build and install
RUN make -j$(nproc) && \
    make install DESTDIR=/netsnmp-install

# Final stage: slim image with just the compiled artifacts
FROM alpine:3.23

# Install runtime dependency (OpenSSL) that net-snmp links against
RUN apk add --no-cache openssl-dev musl-dev

# Copy compiled net-snmp (headers, static libs, shared libs)
COPY --from=builder /netsnmp-install/usr/include/net-snmp /usr/include/net-snmp
COPY --from=builder /netsnmp-install/usr/lib/libnetsnmp* /usr/lib/
COPY --from=builder /netsnmp-install/usr/lib/libsnmp* /usr/lib/

# Ensure shared library cache is updated
RUN ldconfig /usr/lib 2>/dev/null || true